People v. Peterson

IN THE SUPREME COURT OF

CALIFORNIA

THE PEOPLE,

Plaintiff and Respondent,

v.

SCOTT LEE PETERSON,

Defendant and Appellant.

S132449

San Mateo County Superior Court

SC55500

August 24, 2020

Justice Kruger authored the opinion of the Court, in which

Chief Justice Cantil-Sakauye and Justices Chin, Corrigan, Liu,

Cuéllar, and Groban concurred.

PEOPLE v. PETERSON

S132449

Opinion of the Court by Kruger, J.

A jury convicted defendant Scott Lee Peterson of one count

of first degree murder for killing his wife, Laci Peterson, and one

count of second degree murder for killing their unborn son. It

found true the special circumstance that Peterson had

committed multiple murders. At the penalty phase, the jury

returned a verdict of death. This appeal is automatic. (Pen.

Code, § 1239, subd. (b).)

Peterson contends his trial was flawed for multiple

reasons, beginning with the unusual amount of pretrial

publicity that surrounded the case. We reject Peterson’s claim

that he received an unfair trial as to guilt and thus affirm his

convictions for murder. But before the trial began, the trial

court made a series of clear and significant errors in jury

selection that, under long-standing United States Supreme

Court precedent, undermined Peterson’s right to an impartial

jury at the penalty phase. While a court may dismiss a

prospective juror as unqualified to sit on a capital case if the

juror’s views on capital punishment would substantially impair

his or her ability to follow the law, a juror may not be dismissed

merely because he or she has expressed opposition to the death

penalty as a general matter. (See Witherspoon v. Illinois (1968)

391 U.S. 510; Wainwright v. Witt (1985) 469 U.S. 412.) Here,

the trial court erroneously dismissed many prospective jurors

because of written questionnaire responses expressing

opposition to the death penalty, even though the jurors gave no

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Opinion of the Court by Kruger, J.

indication that their views would prevent them from following

the law — and, indeed, specifically attested in their

questionnaire responses that they would have no such difficulty.

Under United States Supreme Court precedent, these errors

require us to reverse the death sentence in this case. (Gray v.

Mississippi (1987) 481 U.S. 648; see People v. Riccardi (2012) 54

Cal.4th 758, 778.) On remand, the People may retry the penalty

phase if they so choose.

I. FACTUAL AND PROCEDURAL BACKGROUND

A. Guilt Phase Trial

1. Prosecution Evidence

Peterson and Laci Rocha met in San Luis Obispo, where

Laci was attending college and Peterson was working in a

restaurant. They married in 1997. They opened and ran a

restaurant together in San Luis Obispo. In 2000, they moved to

Modesto and bought a house. Laci took a job as a substitute

teacher, while Peterson ran a start-up fertilizer company named

TradeCorp U.S.A. out of a leased warehouse. Some years after

the two married, Laci became pregnant; the baby — whom the

couple had named Conner — was due in February 2003.1

On December 23, 2002, Laci went grocery shopping

around midday. She also had a prenatal medical checkup. In

the late afternoon, both Laci and Peterson went to a salon where

Laci’s sister, Amy Rocha, worked. Amy mentioned that she had

1

For clarity, we generally will refer to Laci Peterson (neé

Rocha) and Conner by their first names. We will also sometimes

refer to members of Laci’s immediate family — her mother,

Sharon Rocha; her sister, Amy Rocha; and her brother, Brent

Rocha — by their first names. No disrespect is intended to any

of these individuals.

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ordered a gift basket for a family member that needed to be

picked up the next day by 3:00 p.m. Peterson volunteered to get

it for her, as he was going to be golfing nearby. Peterson also

invited Amy to dinner, but she declined because she had prior

plans. That night, Laci and her mother, Sharon, spoke on the

phone and confirmed that Laci and Peterson would join Sharon

and Sharon’s longtime partner, Ron Grantski, for dinner the

following night, Christmas Eve.

At 10:18 the following morning, a neighbor, Karen Servas,

saw the Petersons’ dog, McKenzie, wandering unaccompanied

on the street, wearing his leash. Peterson’s truck was gone;

Laci’s car was still in their driveway. There were no signs of

activity at the house, so Servas put McKenzie in the Petersons’

backyard and closed the gate. That afternoon, Grantski tried to

reach Laci, without success. Around 3:45 p.m., Amy received a

call that her gift basket had not been picked up. She was unable

to reach Peterson. Neighbors reported Peterson’s truck still

absent at 4:05 p.m., but back by 5:30 p.m.

At around 5:15 p.m., Peterson called Sharon and asked if

Laci was there. He described Laci as “missing.” Sharon

suggested he check with friends and neighbors. Peterson called

Sharon back shortly afterwards and reported the people he had

spoken to had not seen Laci either. Sharon told Grantski to call

the police. Officers soon met Peterson, Sharon, and Grantski at

a nearby park. Neighbors and other relatives gathered at the

park as well. Grantski spoke with Peterson and asked if he had

gone golfing that day. Peterson said he had changed his mind

and gone fishing instead. Told what time Peterson had gone,

Grantski suggested it was an unusually late time to be fishing.

Peterson walked off without responding. Peterson told a cousin

of Sharon’s and two neighbors that he had been golfing all day.

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He volunteered to Sandy Rickard, a friend of Sharon’s, that he

would not be surprised if the police found blood in his truck

because he cut his hands all the time.

Police inspected the Peterson home. There were no signs

of forced entry, nothing appeared missing, and Laci’s purse was

still there. Peterson told officers he and Laci had watched

television that morning, and Laci had planned to walk the dog

and go grocery shopping. Peterson decided to go fishing in the

San Francisco Bay. He went to his company warehouse where

he stored a boat, drove to the Berkeley Marina, fished for two

hours, and quit because the day was cold and rainy. He tried

calling Laci on the home phone and her cell phone but did not

reach her. Peterson got home around 4:30 p.m. He washed his

clothes, ate some pizza, and then called Sharon to track down

Laci.

Officer Matthew Spurlock asked what time Peterson was

fishing. He also asked what Peterson was fishing for and what

lure he used. According to Spurlock and Officer Derrick

Letsinger, Peterson gave slow and initially noncommittal

answers. He “really didn’t give a responsive time” and, when

asked what he was fishing for, paused, gave a blank look, and

“mumbled some stuff” without really answering. Peterson

likewise responded with a blank look when asked about his lure,

but after some delay came up with a size and color description.

Detective Allen Brocchini was called to the Peterson home.

He found wet towels on top of the washing machine. Peterson

explained that he had taken them out so that he could wash the

clothes he had worn that day. Inside the washing machine were

Peterson’s jeans, shirt, and green pullover jacket. In the

bedroom, officers observed a laundry hamper nearly full of

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clothes. With consent, Detective Brocchini examined Peterson’s

truck and saw large patio umbrellas and a tarp in the truck bed.

Inside the truck cab, he found a fishing rod and a bag containing

a package of unused fishing lures and a receipt indicating the

items had all been purchased on December 20. Peterson handed

him a Berkeley Marina parking receipt that indicated Peterson

had entered at 12:54 p.m. On the backseat was a camouflage

jacket Peterson said he had worn fishing that day. Brocchini

and Peterson then went to Peterson’s warehouse. There,

Brocchini observed what he described as a “homemade anchor”

made of concrete in Peterson’s boat, but no long rope to attach it

to the boat.

Peterson agreed to a further interview at the Modesto

police station. Peterson repeated that Laci had planned to walk

the dog and go grocery shopping. For his part, Peterson decided

to go fishing because it was too cold to golf. He went to his

warehouse, then to the Berkeley Marina around 1:00 p.m., and

fished for 90 minutes near an area that was later identified as

Brooks Island.2 Peterson did not pack a lunch or stop to eat on

the way to or from the marina. On the way back, Peterson called

Laci on their home phone and left two messages on her cell

phone.3 He dropped off his boat at the warehouse and went

2

Peterson said he left the house with no jacket on, put on a

green pullover jacket, and then put the camouflage jacket over

that when it started raining. The camouflage jacket, when

Detective Brocchini saw it in Peterson’s truck a few hours later,

was dry.

3

When messages on Laci’s cell phone were played, only one

voice message from Peterson was found.

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home. Peterson told officers that there were no problems in his

marriage.

Peterson had a followup interview with Detective Craig

Grogan and an investigator from the state’s Department of

Justice on Christmas Day, December 25. Peterson explained

that he had never fished on the San Francisco Bay before but

wanted to test out his boat. He troll fished4 for an hour on the

way out to Brooks Island from the marina dock. Peterson

suggested Laci might have been robbed of her jewelry by a

transient and then kidnapped. He denied being involved in an

affair with anyone. Later that day, Peterson called Detective

Brocchini to check on the investigation. He asked if the police

would be using cadaver dogs5 to search for Laci. Brocchini

explained that they would not, because no one assumed Laci was

dead.

In the days after Christmas, the Modesto Police

Department executed search warrants on the Peterson home

and Peterson’s warehouse. Police confirmed that there had been

no forced entry at the house. None of Laci’s jewelry was missing,

other than one pair of diamond earrings. Traces of Peterson’s

blood were found on a comforter in the master bedroom. In

sheds in the backyard, police found the cover to Peterson’s boat,

smelling heavily of gasoline,6 as well as a blue tarp. The boat

cover had chunks of concrete in it. In Peterson’s truck, police

4

Troll fishing involves dragging a baited line through the

water.

5

Cadaver dogs are trained to scent and alert to

decomposing human remains.

6

At trial, evidence was introduced that gasoline makes it

extremely difficult for trailing dogs to identify a human scent.

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found additional spots of Peterson’s blood. Peterson explained

that he had cut his hand on the truck door. Police found small

chunks of cement and a claw hammer with cement powder on it

in the truck’s bed.

At the warehouse, the police inspected the boat and found

a pair of pliers under the middle seat. The pliers had hair

clamped in their teeth. Subsequent mitochondrial DNA testing

of a hair fragment determined that the hair matched a reference

sample from Sharon, which meant that its donor had the same

maternal lineage as Sharon. The hair did not match Peterson’s.

During the search of the Peterson home, articles that Laci

would have touched were collected to give to trailing dogs to

enable them to search for Laci’s scent. These included a slipper

and a pair of sunglasses. On December 28, four days after Laci

disappeared, Trimble, a trailing dog, was presented Laci’s

sunglasses at the Berkeley Marina. Trimble alerted to Laci’s

scent along a path that led out onto a dock and ended at the

water.

On December 30, a woman named Amber Frey contacted

the police after a friend advised her that Peterson, who she

thought was unmarried with no children, and with whom she

had been having a relationship since November, was connected

to the disappearance of his pregnant wife. Frey and Peterson

had had their first date on November 20 and had immediately

become sexually intimate. Their relationship had progressed to

the point where Peterson had stayed over at Frey’s home, picked

up Frey’s young daughter from daycare, gone to various parties

with Frey, alone and with her daughter, picked out a Christmas

tree with Frey, and discussed their views on having children.

Peterson initially told Frey he had never been married and had

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no children, but on December 6 a friend of Frey’s discovered

otherwise and gave him an ultimatum to tell Frey by December

9 or else she would. On December 9, Peterson explained to Frey

that he had in fact been married, but had “lost” his wife, and the

upcoming holidays would be his first without her. On December

15, Peterson told Frey he would be in Europe on business

through the rest of the month and much of January. On

December 23, after Frey asked where she should send him

things while he was away, Peterson rented a private mailbox to

which Frey could send letters. He called Frey that day, claiming

to be in Maine duck hunting with his father, and again on

Christmas Day, supposedly still from Maine.

After meeting with police, Frey agreed to cooperate and

tape future calls from Peterson. On New Year’s Eve, Peterson

called Frey from a vigil for Laci, claiming to be in Paris watching

fireworks over the Eiffel Tower. He called Frey again on New

Year’s Day and in the days after, maintaining the fiction that he

was in Europe. On January 3, 2003, when police confronted

Peterson with a picture of himself and Frey, Peterson denied

that it was him in the photo and that he was having an affair.

On January 6, at the instigation of police, Frey dropped

hints that a friend had learned the truth and would tell her in a

matter of hours.7 In response, Peterson finally admitted to Frey

that he was married to a woman named Laci and had been in

Modesto the entire time. The next day, when Frey asked if

Peterson had told Laci about her, Peterson said he had and that

7

Laci’s disappearance swiftly became the subject of

widespread media attention. To maintain the pretense that she

did not know the truth about Peterson yet, Frey denied watching

the news.

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Laci was “fine” with his having an affair. Later in the month,

once news media had made the affair public, Peterson, in an

interview aired nationwide, repeated that Laci was fine with his

having an affair and said he had disclosed the affair to the police

immediately. On February 19, at the direction of police

investigators, Frey told Peterson they should stop talking.

In January, after obtaining a warrant, police placed a

surveillance camera outside the Peterson home and GPS

tracking devices on Peterson’s vehicles, including a series of cars

and trucks Peterson rented for a few days at a time.

Surveillance data from these devices and visual surveillance by

the police showed Peterson driving the approximately 90 miles

from his home to the Berkeley Marina at least five times in

January, each time using a different vehicle. On January 5, he

drove there in a gray Subaru, spent five or ten minutes, and left.

On January 6, he returned to the marina in a red Honda and

again spent only a few minutes. On January 9, Peterson drove

there in a white pickup truck. On January 11, after determining

that their cover had been blown, the Modesto Police Department

shut down surveillance at the Peterson home. Nonetheless,

from tracking data supplied by the automobiles’ manufacturers,

police were able to determine that Peterson returned to the

marina on January 26 in Laci’s Land Rover and on January 27

in a rented Dodge Dakota.

During the same period, Peterson began to make various

changes to his work and living situations. On January 13,

Peterson gave 30 days’ notice that he was terminating his

warehouse lease, which was not up until October. That same

month, he started discussions to sell the Peterson home. On

January 29, Peterson sold Laci’s car, trading it in for a Dodge

Dakota pickup truck. On January 30, he stopped home mail

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delivery and directed that all mail be delivered to the post office

box he had set up on December 23. The nursery for Conner was

converted into storage space. On February 18, satellite

television service to the Peterson home was canceled; the

satellite company’s records indicated the customer had

explained he was moving overseas.

A $500,000 reward was posted by a private foundation for

information leading to Laci’s return. For months, no useful

leads turned up. Even when potentially promising sightings

were reported, Peterson appeared to show little interest. For

example, the prosecution presented evidence collected from an

authorized wiretap of Peterson’s phone that showed he took

days to follow up with police about a possible sighting in

Washington, though he told others — including his mother —

that he had followed up with police immediately. Peterson

similarly told a business associate he was waiting near the

airport in case he needed to fly up to Washington, though at the

time, Peterson was not near any airport.

In mid-April, a significant storm hit the San Francisco Bay

Area. On April 13, after the storm had passed, a couple walking

their dog came upon Conner’s badly decomposed body,

apparently washed ashore along with other storm debris. The

location was just over a mile from the southern tip of Brooks

Island. The next morning, Laci’s body was discovered on the

shoreline at Point Isabel, south of Conner’s body and again just

over a mile from Brooks Island. Laci’s body had barnacles and

duct tape on it. From residual clumps of fabric, it was possible

to determine that she had been wearing light-colored capris.

The clothing was consistent with the recollection of Amy, who

testified that Laci was wearing cream-colored pants when she

last saw her sister on December 23. It was, however,

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inconsistent with the recollection of Peterson, who told police

that Laci was wearing black pants when he last saw her on

December 24. Days later, DNA testing confirmed the identities

of the two bodies.

Dr. Brian Peterson (no relation to the Petersons)

performed autopsies on both bodies. Laci’s body had several

parts missing, including her head, forearms, and one lower leg.

Changes to the tissue suggested her body had been in a marine

environment. Tidal action and marine animals could explain

the missing body parts. Laci’s uterus was still enlarged, her

birth canal was closed, and there was no evidence of a

Caesarian-section birth, which indicated she had died while still

pregnant. Dr. Allison Galloway, a forensic anthropologist given

the remains to analyze, testified that Laci had been in water for

three to six months. Given the condition of the body, it was not

possible to determine a cause of death.

Conner’s body was intact. There was tape on his neck but

no associated injuries, which led Dr. Peterson to conclude the

tape was just debris that had become attached to Conner after

his death. There was no clothing on the body. Conner still had

part of his umbilical cord and meconium in his intestines, which

indicated he had died before birth. Based on his size and the

softness of his tissue, Dr. Peterson opined that Conner must

have remained protected inside Laci’s uterus for some time after

death; had he spent a significant period of time exposed in the

water, he would have been eaten by marine animals.

As mentioned, Laci had had a prenatal checkup on

December 23. Based on ultrasounds, Conner was at 32 to 33

weeks of gestation. Post-mortem measurements of his bone

growth allowed Dr. Greggory DeVore to estimate Conner’s date

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of death as falling between December 21 and December 24, with

an average of December 23. Both Dr. Esther Towder, Laci’s

gynecologist who conducted the December 23 checkup, and

Dr. Peterson testified that based on his age and health, Conner

would have survived had he been born that day.

Dr. Ralph Cheng, a hydrologist with the United States

Geological Survey, was contacted by the Modesto Police

Department in February, while Laci was still missing, and again

in May, after she and Conner had been found. The first time, he

was asked to assume that Laci’s body had been dumped with

weights into the San Francisco Bay and, based on that

assumption, to estimate where the body might be found. The

second time, after the bodies had been found, Dr. Cheng was

asked to estimate where they might have originated. He was

able to estimate a location for Conner near the southern tip of

Brooks Island, but no likely location for Laci. Divers searching

the bay at Dr. Cheng’s target location were unable to find any

relevant evidence.

On April 12, the day before Conner’s body was found,

Peterson bought a car using his mother’s name, Jacqueline, as

his own, providing a fake driver’s license number, and paying

$3,600 in cash. He had grown a goatee and mustache and

appeared to have dyed his hair. On April 15, when Sharon

called him about the discovery of the (as-yet unidentified) bodies

of Conner and Laci, Peterson did not return her call. Believing

Peterson might flee, police arrested him on April 18. When

arrested, Peterson had nearly $15,000 in cash, foreign currency,

two drivers’ licenses (his own and his brother’s), a family

member’s credit card, camping gear, considerable extra clothing,

and multiple cell phones.

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The prosecution introduced evidence concerning the

Petersons’ finances. The Petersons’ expenses were high in

relation to their current income. TradeCorp U.S.A. had never

been profitable, posting operating losses of $40,000 and

$200,000 in consecutive years; the company was not meeting

sales goals, and it owed its parent company $190,000. Peterson

had signed multiple credit card applications in the company’s

name containing misrepresentations as to the company’s

income.

In fall 2002, Laci inherited jewelry and, at Peterson’s

request, had some of the items appraised. They were valued at

more than $100,000. Computers seized from the Peterson home

and the warehouse showed e-mails sent from an account bearing

the username “slpete1” discussing the sale of jewelry, and eBay

records likewise showed Peterson had posted jewelry items for

sale. Laci also stood to inherit one-third of the proceeds from

the sale of her grandfather’s house, an interest estimated to be

worth around $140,000. Laci’s interest would terminate on her

death, with no right of survivorship to Peterson, but it was

unclear whether Peterson was aware of the limitation; Brent,

the cotrustee of the grandparents’ estate, had not told Peterson

about the provision.

The prosecution also submitted additional background

concerning Peterson’s fishing. Computers seized from the

Peterson home and the warehouse showed that someone had

conducted searches of classified advertisements for boats on

December 7, the day after Peterson learned he would no longer

be able to conceal his marriage from Frey. That same day,

Peterson called Bruce Peterson (no relation) about a boat for

sale. Peterson inspected the boat the next day and bought it on

December 9, without the anchors that came with the boat.

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Peterson never registered the boat, nor did he ever mention the

purchase to his father; to Grantski, an avid fisherman who had

invited Peterson to fish several times; to other members of the

Rocha family; or to his friend Gregory Reed, with whom he

frequently discussed fishing. Review of the seized computers’

browser histories also showed someone conducting searches on

December 8 for boat ramps on the Pacific Ocean, then examining

nautical charts, currents, and maps for the Berkeley Marina and

San Francisco Bay, including the area around Brooks Island.

There were also visits to fishing-related websites.

December 24, the day Peterson said he was fishing, was

gray, damp, and cold with a bit of wind. Few people were at the

Berkeley Marina. When questioned by police, Peterson would

not say what he was hoping to catch, but the fishing searches

performed from his computer earlier in the month had included

searches relating to sturgeon and striped bass. Angelo

Cuanang, a published author on fishing in the San Francisco

Bay who was accepted by the court as an expert fisherman,

testified that Brooks Island was the wrong place to seek

sturgeon, which congregated in a different part of the bay that

time of year. Sturgeon also preferred live bait to lures, and

Peterson’s rod was too weak to catch them. Anchoring was

essential to reel in sturgeon; the homemade cement anchor in

his boat would have been inadequate. Finally, it was illegal to

troll for sturgeon, as Peterson claimed to have done. Peterson’s

lures and the time of year he was fishing were also wrong for

catching striped bass.

The prosecution’s theory was as follows: Peterson killed

Laci sometime on the night of December 23 or morning of

December 24. On the morning of the 24th, Peterson let their

dog McKenzie out with his leash on to make it appear something

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had happened while Laci was walking him. He wrapped Laci’s

body in a tarp in the bed of his truck, covered her with the patio

umbrellas, drove to the warehouse, and then moved her body

into his boat.8 He drove to the Berkeley Marina, motored out to

an area near Brooks Island, and slipped her body, attached to

homemade concrete weights like the homemade anchor

Peterson had made, into the bay.9 Peterson then returned to

Modesto, dropped off the boat at the warehouse, put the boat

cover out back under a leaky gas blower so that any scent would

be obscured, washed his clothes, and proceeded with the ruse

that Laci was missing, hoping her body would never be

discovered.

2. Defense Evidence

The defense argued the police had not diligently pursued

whether a person or persons other than Peterson were more

likely responsible for Laci’s disappearance and murder. The

defense presented evidence that a burglary had occurred on the

Petersons’ street the week of her disappearance and argued that

the police failed adequately to follow up on whether that

burglary had any connection to Laci’s disappearance. It also

presented evidence that a stranger had gone to several houses

on December 23 asking for money and, one neighbor thought,

casing houses for burglaries, and so might have had something

to do with her disappearance. Testimony was presented that

8

The prosecution introduced photographs of a district

attorney’s office employee, at approximately the same stage of

pregnancy and weight as Laci at her disappearance, fitting into

the bottom of Peterson’s boat.

9

Through an engineer for the company that manufactured

the boat, the prosecution introduced stability tests the boat

model underwent to obtain certification before it was sold.

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the same neighbor, walking with a police officer on Christmas

Day to look for the stranger, had seen a pair of sandals lying in

the road 150 feet from the Petersons’ home; the neighbor

wondered at the time if they might have any connection to Laci’s

disappearance, but the officer just left them there. To support

the possibility of a third party’s involvement, the defense

challenged the prosecution’s theory that Conner died December

23 or 24, presenting its own expert who testified based on

ultrasounds and other evidence that Conner lived until after

Christmas.

The defense also sought to challenge other aspects of the

prosecution’s case. To rebut the dog-trailing evidence, the

defense called Ronald Seitz, a second dog handler who also had

his dog try to find Laci’s scent at the Berkeley Marina on

December 28. The dog, T.J., was given Laci’s slipper as a scent

object, but discovered no scent trail. To rebut the inference that

Peterson had a financial incentive to kill Laci, the defense

presented a financial expert who testified that TradeCorp

U.S.A. and the Petersons were both reasonably financially

healthy. To portray the prosecution’s theory as physically

impossible, the defense also sought to introduce video of a

demonstration with a weighted 150-pound dummy in a boat on

the bay in which a defense firm employee, trying to dump the

dummy out, sank the boat. As will be discussed below, the trial

court excluded the video.

The defense offered explanations for the circumstances of

Peterson’s behavior in April. His use of his mother’s name to

purchase a car was at her suggestion, to avoid having it

impounded. He had large amounts of cash because she gave it

to him to reimburse him for money erroneously withdrawn from

his bank account rather than hers. Finally, he had his brother’s

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driver’s license because the club where he was going to golf that

day gave discounts for local residents such as his brother.

3. Guilt Phase Verdict

The jury found Peterson guilty of murder in the first

degree for killing Laci and murder in the second degree for

killing Conner. (See Pen. Code, §§ 187, 189.) It found true the

sole charged special circumstance, for multiple murder. (See id.,

§ 190.2, subd. (a)(3).)

B. Penalty Phase Trial

1. Prosecution Evidence

Peterson had no criminal record nor any history of violent

acts. At the penalty phase, the prosecution relied exclusively on

the circumstances of the crime and victim impact evidence.

Four members of Laci’s immediate family — her mother,

Sharon; her stepfather, Ron Grantski; her brother, Brent; and

her sister, Amy — testified. They described who Laci was as a

person, shared photographs, memories, and vignettes from her

life, and conveyed the grief and loss they each felt after the

deaths of Laci and her unborn child.

2. Defense Evidence

Through friends, family, neighbors, teachers, coworkers,

employers, and other witnesses, the defense offered evidence

that Peterson had been a kind and positive member of the

community. Peterson grew up in a loving family, displayed a

patient and gentle disposition, and was a solid student. As part

of his high school community service requirement, Peterson

worked at a home for the elderly and tutored homeless children.

He started his own business and worked a variety of other jobs

while in college.

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According to the defense, Peterson was always calm with

Laci. Indeed, witnesses testified Peterson was calm at all

times — at work, on the golf course, and in his dealings with all

those around him.

Friends and family testified to the impact the trial had

had on Peterson’s relatives and indicated they believed, if

sentenced to life in prison, Peterson could make a positive

impact on the lives of others.

In closing argument, defense counsel described Peterson’s

life as one worth saving and argued that lingering doubt about

Peterson’s guilt should also weigh in favor of a life verdict.

3. Penalty Phase Verdict and Sentence

The jury returned a death verdict. The court denied a

motion for new trial, denied the automatic motion for

modification of the verdict, and imposed a sentence of death.

II. DISCUSSION

A. Excusal of Prospective Jurors for Cause Based

on Questionnaire Answers Reflecting

Opposition to the Death Penalty

Peterson claims errors occurred during every phase of his

trial. We begin with his challenge to the manner in which the

jury was chosen. During jury selection, multiple prospective

jurors were excused based solely on written questionnaire

responses indicating they were personally opposed to the death

penalty. Peterson contends that, absent any indication these

jurors would be unable to faithfully and impartially apply the

law, it was error to remove them from the juror pool.

On this initial point, Peterson is correct. Long-standing

United States Supreme Court precedent makes clear that

prospective jurors may not be disqualified from service in a

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Opinion of the Court by Kruger, J.

capital case solely because of their general objections to the

death penalty. (See Witherspoon v. Illinois, supra, 391 U.S. at

pp. 518–523 (Witherspoon); Wainwright v. Witt, supra, 469 U.S.

at p. 424 (Witt).) That is just what happened here. And as this

court has repeatedly explained, under high court precedent,

even one such error requires “automatic reversal of any ensuing

death penalty judgment.” (People v. Heard (2003) 31 Cal.4th

946, 966–967; accord, e.g., People v. Armstrong (2019) 6 Cal.5th

735, 764; People v. Woodruff (2018) 5 Cal.5th 697, 745; People v.

Riccardi, supra, 54 Cal.4th at p. 783.) Here, there was not just

one error; there were many. We are therefore required to

reverse the death judgment. Contrary to Peterson’s argument,

however, we are not also required to reverse the judgment of

guilt.

Jury selection in a capital case typically begins with

prospective jurors filling out written questionnaires. These

questionnaires allow the court and counsel to explore potential

jurors’ views and past experiences that might affect how they

evaluate the evidence to be presented. They also address views

a juror might have concerning the death penalty, in the event a

defendant is found guilty and findings are made that would

render him or her eligible to be punished by death. The

questionnaire in this case, based on proposals from the parties

and as approved by the court, contained roughly 120 questions

on a range of topics, including 13 directed to potential jurors’

views on the death penalty. To supplement the picture painted

by answers to written questionnaires, the court and counsel may

ask prospective jurors individual questions orally to clarify the

nature of any views and further evaluate their ability to serve,

a process known as voir dire. (See People v. Armstrong, supra,

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Opinion of the Court by Kruger, J.

6 Cal.5th at p. 749; Hovey v. Superior Court (1980) 28 Cal.3d 1,

80–81.)

Prospective jurors may be excused from jury service

through one of two primary mechanisms. First, the court may

excuse jurors for cause based on a determination that bias or

another substantial impairment disqualifies them from service.

In a capital case, prospective jurors are subject to excusal if they

would be unable or unwilling to impose the death penalty (or,

conversely, if they would be unable or unwilling to vote against

death) should the defendant be found guilty. (See, e.g., Ross v.

Oklahoma (1988) 487 U.S. 81, 83–86; Lockett v. Ohio (1978) 438

U.S. 586, 595–596.) Second, prospective jurors may be excused

by the parties by means of peremptory challenge. Each party is

given a number of peremptory strikes set by law and allowed to

cull from the remaining pool, up to the limit of their strikes,

additional potential jurors they believe would be less favorably

disposed to their side and to the verdict they seek. The result of

this process is a final jury of 12, plus alternates to guard against

the need to excuse one or more jurors during trial itself.

We are concerned here only with the first mechanism,

excusal for cause. The question is whether the process the trial

court employed to remove jurors complied with the standards

the United States Supreme Court has established for the

disqualification of jurors for bias in a capital case.

More than half a century ago, the United States Supreme

Court held in Witherspoon, supra, 391 U.S. at page 522, that “a

sentence of death cannot be carried out if the jury that imposed

or recommended it was chosen by excluding veniremen for cause

simply because they voiced general objections to the death

penalty or expressed conscientious or religious scruples against

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Opinion of the Court by Kruger, J.

its infliction.” The court explained the reason for this rule: “A

man who opposes the death penalty, no less than one who favors

it, can make the discretionary judgment entrusted to him by the

State and can thus obey the oath he takes as a juror. But a jury

from which all such men have been excluded cannot perform the

task demanded of it,” namely, to “express the conscience of the

community on the ultimate question of life or death.” (Id. at

p. 519.) Put differently, “a criminal defendant has the right to

an impartial jury drawn from a venire that has not been tilted

in favor of capital punishment by selective prosecutorial

challenges for cause” based solely on general opposition to the

death penalty. (Uttecht v. Brown (2007) 551 U.S. 1, 9.)

The law also recognizes, however, that states must have a

way to ensure capital cases are tried before juries “able to apply

capital punishment within the framework state law prescribes.”

(Uttecht v. Brown, supra, 551 U.S. at p. 9.) In Witt, supra, 469

U.S. 412, the court held that trial courts may excuse a

prospective juror for cause based on the juror’s views of capital

punishment if those views “would ‘prevent or substantially

impair the performance of his duties as a juror in accordance

with his instructions and his oath.’ ” (Id. at p. 424, quoting

Adams v. Texas (1980) 448 U.S. 38, 45; accord, People v. Jones

(2017) 3 Cal.5th 583, 614.) But to protect the right to trial by

impartial jury, a trial court may not remove jurors for cause

based on views that do not substantially impair their ability to

serve. “[I]f prospective jurors are barred from jury service

because of their views about capital punishment on ‘any broader

basis’ than inability to follow the law or abide by their oaths, the

death sentence cannot be carried out.” (Adams, at p. 48; accord,

Uttecht, at p. 9; Jones, at p. 614.)

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Opinion of the Court by Kruger, J.

Taken together, Witherspoon and Witt make clear that

prospective jurors may not be disqualified from service simply

because they object to the death penalty as a general matter.

“[N]ot all who oppose the death penalty are subject to removal

for cause in capital cases; those who firmly believe that the

death penalty is unjust may nevertheless serve as jurors in

capital cases so long as they state clearly that they are willing

to temporarily set aside their own beliefs in deference to the rule

of law.” (Lockhart v. McCree (1986) 476 U.S. 162, 176.) Nor may

a juror be disqualified from service because he or she might

“impose a higher threshold before concluding that the death

penalty is appropriate.” (People v. Stewart (2004) 33 Cal.4th

425, 447.) “The critical issue is whether a life-leaning

prospective juror — that is, one generally (but not invariably)

favoring life in prison instead of the death penalty as an

appropriate punishment — can set aside his or her personal

views about capital punishment and follow the law as the trial

judge instructs.” (People v. Thompson (2016) 1 Cal.5th 1043,

1065.) If a juror can obey those instructions and determine

whether death is appropriate based on a sincere consideration

of aggravating and mitigating circumstances, the juror may not

be excused for cause. (People v. Armstrong, supra, 6 Cal.5th at

p. 750; Stewart, at p. 447; People v. Lewis (2001) 25 Cal.4th 610,

633.)

Here, Peterson directs our attention to a group of

prospective jurors who were excused based solely on their

questionnaire answers, without further questioning by the court

or counsel. When dismissal is based solely on the written record,

we independently review whether that record establishes that a

juror was categorically unable to serve. (People v. Woodruff,

supra, 5 Cal.5th at p. 743; People v. Riccardi, supra, 54 Cal.4th

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Opinion of the Court by Kruger, J.

at p. 779.) “ ‘[W]hen an excusal was based on questionnaire

responses alone, the excusal may be upheld if those answers,

“taken together,” clearly demonstrate the juror’s unwillingness

or inability, because of attitudes about the death penalty, to

perform his or her duties in a capital trial.’ ” (Riccardi, at

p. 779.)

The record reveals that many jurors were summarily

excused based on their responses to a single question, No. 109:

“How would you rate your attitude towards the death penalty?”

That question gave prospective jurors six possible answers —

Strongly Oppose, Oppose, Weakly Oppose, Weakly Support,

Support, and Strongly Support — and spaces to mark which one

of these most closely reflected their general attitude. Although

the prospective jurors’ answers to this question could well have

prompted further inquiry during voir dire, these answers alone

offered little insight into the controlling issue for purposes of

their qualification to serve as jurors — whether they, whatever

their general views on the death penalty might be, could accept

and follow the court’s instructions and be able to choose either

life or death based on a sincere consideration of any aggravating

or mitigating circumstances. (People v. Armstrong, supra, 6

Cal.5th at p. 750.) On that issue, a second question, No. 115,

was more illuminating. It asked: “Do you have any moral,

religious, or philosophical opposition to the death penalty so

strong that you would be unable to impose the death penalty

regardless of the facts?”10

10

A related question, No. 116, screened for jurors on the

other end of the spectrum. It asked: “Do you have any moral,

religious, or philosophical beliefs in favor of the death penalty

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Opinion of the Court by Kruger, J.

Peterson asks us to focus in particular on 13 prospective

jurors who were excused without further questioning after

expressing some degree of opposition to the death penalty in

response to question No. 109, even though these same jurors

also answered “no” to question No. 115 — meaning that, so far

as their questionnaires revealed, none held views so strong that

they would be unable to vote for death if the circumstances

warranted. The trial court dismissed these 13 prospective jurors

as not qualified to serve without, insofar as the record reveals,

ever probing their views on the ultimate issue, whether they

were substantially impaired.

Take, for example, Prospective Juror No. 4841. Asked in

her questionnaire her feelings toward the death penalty, the

juror wrote: “Have no feeling.” Two questions later, asked to

rate her attitude toward the death penalty and given the

aforementioned range of options from “Strongly Oppose” to

“Strongly Support,” she checked “Strongly Oppose.” But in

response to the additional question, “Do you have any moral,

religious, or philosophical opposition to the death penalty so

strong that you would be unable to impose the death penalty

regardless of the facts?” (italics added), the prospective juror

checked “No.” Indeed, the juror implicitly confirmed that in

some instances she could impose the death penalty; asked

whether it would “be difficult for you to vote for the death

penalty if the crime was the guilty party’s first offense?,” she

checked “No.”

Discussing the juror and whether counsel would stipulate

to her excusal, the court said: “Reading these [questionnaire

so strong that you would be unable to impose life without

possibility of parole regardless of the facts?” (Italics added.)

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Opinion of the Court by Kruger, J.

answers], I am of the opinion this juror wouldn’t qualify. [¶]

Look at 4841. Go to that one. 19 — page 19, answer 109.

Strongly opposes the death penalty. I could dispose of this juror

in a couple of questions. So if you don’t want to stipulate, fine.

But if they oppose the death penalty, they are not qualified

under Wainwright [v.] Witt.” That afternoon, the trial court

read off the juror’s answer to the attitude question, No. 109,

again noting that she had checked, “Strongly Opposed.” On that

basis, he concluded “this juror . . . would not qualify” and

excused her without any questioning.

In response to these same questions, Prospective Juror

No. 6960 said of the death penalty, “I wish it was not a thing

needed” and checked that she opposed (not that she strongly

opposed) the death penalty. But she too indicated on the very

next page that her opposition to the death penalty was not such

as would render her “unable to impose the death penalty

regardless of the facts.” Based on these answers, the court

described the juror as “one who is opposed to the death penalty

without qualification” and concluded it would “excuse 6960 for

cause, because that juror is opposed to the death penalty,

without reservation.”

Prospective Juror No. 16727 indicated he was strongly

opposed to the death penalty based on his “spirituality,” but his

opposition was not such that he could never impose it no matter

the facts. His questionnaire indicated that, if the crime was a

defendant’s first offense, whether it would be difficult to vote for

death would “[d]epend[] on the [e]vidence” — implying the juror

could, in some instances, vote for death even for a first-time

offender. The trial court, noting that the juror wrote he was

“against the death penalty” and checked that he “strongly

oppose[d]” it, said, “I don’t think this person would qualify

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PEOPLE v. PETERSON

Opinion of the Court by Kruger, J.

because of his answers, and he’s opposed to the death penalty.

So I would be inclined to excuse him. Over the objection of

[defense counsel].” After defense counsel confirmed his

“vehement objection,” the court excused the juror without

questioning him: “[J]uror number 16727 is excused because he

is opposed to the death penalty.”

Again, these were not isolated occurrences. The trial court

excused more than a dozen prospective jurors based solely on

their written opposition to the death penalty (question No. 109),

without also considering their answers to question No. 115,

which reflected the jurors’ ability to impose the death penalty in

some circumstances. Perhaps further questioning might have

established that one or more of these jurors in truth could not

conscientiously consider death as an option. But no such

questioning occurred here, because the trial court rejected

counsel’s requests to question these prospective jurors and

declined to ask any questions itself. As a result, these jurors

were excused for cause based on a written expression of

opposition to the death penalty, without more.

We do not suggest that a trial court errs any time it

exercises its discretion to limit counsel’s opportunity to question

prospective jurors directly. In a case with a venire of this size —

nearly 1,500 prospective jurors — tight controls on voir dire

were necessary and inevitable. But a court must still ensure

that, by whatever means, sufficient inquiry is made so only

those properly excusable under the governing standards are

dismissed for cause: “ ‘Before granting a challenge for cause, the

“court must have sufficient information regarding the

prospective juror’s state of mind to permit a reliable

determination as to whether the juror’s views would ‘ “prevent

or substantially impair” ’ ” performance as a capital juror.

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Opinion of the Court by Kruger, J.

[Citation.] Trial courts must therefore make “a conscientious

attempt to determine a prospective juror’s views regarding

capital punishment to ensure that any juror excused from jury

service meets the constitutional standard.” ’ ” (People v.

Buenrostro (2018) 6 Cal.5th 367, 412.) Sufficient inquiries were

not made in this case.

The People concede Peterson’s claims are all preserved

because at the time of trial no objection was required to preserve

claims of Witt/Witherspoon error. (See People v. Jones (2013) 57

Cal.4th 899, 914–915 [describing evolution of the forfeiture rule

for such error].) In any event, the record shows defense counsel

consistently resisted these dismissals, arguing on numerous

occasions that just because a juror indicated opposition to the

death penalty, that did not mean he or she could not vote for

death in appropriate circumstances. These objections gained no

traction with the trial court, and ultimately the defense had no

choice but to accede to the for-cause standard the court had

adopted: “Obviously[,] I believe that opposition to the death

penalty should not be a for-cause challenge. The Court has ruled

on it. I’m not going to continue to raise it each time. Although

I want the record to reflect that I am submitting [subject to a

standing objection] on the Court’s previous rulings.”

Crucially, “it is the adversary seeking exclusion who must

demonstrate, through questioning, that the potential juror lacks

impartiality.” (Witt, supra, 469 U.S. at p. 423; accord, People v.

Stewart, supra, 33 Cal.4th at p. 445.) It is thus incumbent on

the party seeking excusal, or the court, to ask questions

sufficient to differentiate between mere opposition and an actual

inability to impose the death penalty. The exclusion of

prospective jurors as impaired, in the absence of a record

demonstrating they were impaired, is a violation of the Sixth

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Opinion of the Court by Kruger, J.

Amendment right to an impartial jury. (See People v. Woodruff,

supra, 5 Cal.5th at pp. 744–745 [error not to ask clarifying

questions to determine whether written indication of opposition

to the death penalty would impair juror’s ability to serve]; People

v. Riccardi, supra, 54 Cal.4th at p. 782 [same]; Stewart, at

pp. 449–452 [same].)

Even though neither the court nor the prosecution

questioned these 13 excused jurors, the People argue that all 13

dismissals are supported by substantial evidence in the record.

Given the absence of questioning, the People rely solely on the

jurors’ questionnaire responses. In addition to the opposition to

the death penalty reflected in the jurors’ answers to question

No. 109, the People point to other responses to questions about

the jurors’ death penalty attitudes — for example, that in many

cases their views had not changed in the last 10 years, or that

some jurors anticipated it would be difficult for them to choose

death for a first-time offender.

There are two difficulties with the People’s response. The

first is that it misstates the standard of review; as discussed,

when dismissal for cause based on an inability to impose the

death penalty rests solely on written questionnaire answers, we

review the record de novo, rather than under the deferential

substantial evidence standard. (People v. Woodruff, supra, 5

Cal.5th at p. 743.) The second, more fundamental difficulty is

that nothing in the prospective jurors’ questionnaire responses

establishes that the jurors would have been unable to follow the

law and impose the death penalty if circumstances warranted,

which is the only relevant question under high court precedent.

There is no dispute that each of the 13 prospective jurors

opposed the death penalty, sometimes strongly so. But the issue

is whether that opposition would have disabled them from

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Opinion of the Court by Kruger, J.

following the court’s instructions and ever imposing the death

penalty. On that point, in response to question No. 115, all 13

prospective jurors expressly indicated their death penalty views

were not so strong that they would be unable to impose the

death penalty. That answer required further inquiry before the

court could conclude these jurors were impaired. (See People v.

Leon (2015) 61 Cal.4th 569, 592–593.)

In sum: The law is clear that a capital jury may include

those who, as an abstract matter, oppose — or even strongly

oppose — the death penalty, though a prosecutor might seek to

limit the number of such jurors. It may include those who

favor — or even strongly favor — the death penalty, though

defense counsel might seek to limit their numbers. Eligibility

for service does not depend on a juror’s abstract views of capital

punishment. It depends, instead, on the prospective juror’s

willingness and ability to follow a court’s instructions and

conscientiously consider both penalties in light of the evidence

presented by each side. This is the meaning of the guarantee of

an impartial jury, drawn from the community at large, for the

trial of a defendant facing the death penalty.

Under that standard, the questionnaire answers

submitted by these prospective jurors did not establish they

were unfit to serve. Voir dire might have painted a different

picture, with the court and counsel through oral questions

exploring whether each individual juror had the necessary

ability and willingness to consider both life and death as options.

But for these 13 jurors, there was no such questioning. Thus,

we know only that in the abstract they opposed the death

penalty. The record made in the trial court does not offer a basis

sufficient to uphold excusal of these jurors for cause under the

clear standards laid out by the United States Supreme Court.

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Opinion of the Court by Kruger, J.

The People contend these errors in jury selection should

be treated as harmless. But precedent requires otherwise.

Witherspoon itself held “that a sentence of death cannot be

carried out” if it has been imposed by a jury chosen after

disqualifying prospective jurors for having “voiced general

objections to the death penalty.” (Witherspoon, supra, 391 U.S.

at p. 522.) The United States Supreme Court has since

instructed that even a single erroneous exclusion of a

prospective juror based solely on his or her general views about

the death penalty requires that any death sentence thereafter

imposed be set aside. (Gray v. Mississippi, supra, 481 U.S. at

p. 665 (plur. opn. of Blackmun, J.) [“The nature of the jury

selection process defies any attempt to establish that an

erroneous Witherspoon-Witt exclusion of a juror is harmless”];

see id. at p. 672 (conc. opn. of Powell, J.); see People v. Riccardi,

supra, 54 Cal.4th at p. 778 [Witherspoon-Witt error “requires

automatic reversal of defendant’s sentence of death under

existing United States Supreme Court precedent”].) Here, the

trial court excluded no fewer than 13 jurors based on their

general views about the death penalty, even though all 13

attested that their views would not prevent them from following

the law. The death sentence must be reversed, and the People

given another opportunity to seek that penalty before a properly

selected jury if they so choose.

In their brief, the People asked us to reconsider our cases,

including principally People v. Riccardi, supra, 54 Cal.4th 758,

that hold the erroneous exclusion of a juror based on death

penalty views can never be harmless. But at oral argument, the

People acknowledged that Gray v. Mississippi, supra, 481 U.S.

648 is controlling and that error of this sort requires automatic

reversal of the penalty judgment. (See People v. Armstrong,

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Opinion of the Court by Kruger, J.

supra, 6 Cal.5th at p. 764.) Riccardi is but one in a long line of

cases, dating back to Witherspoon itself, that have held that

reversal is required.

In applying these rules here, we break no new ground; the

governing law was as clear at the time of trial as it is today.

Indeed, in a case decided several months before jury selection

began in this case, we pointedly reminded trial judges about the

critical importance of carefully adhering to the well-settled

standards and procedures for death-qualifying a jury: “In view

of the extremely serious consequence — an automatic reversal

of any ensuing death penalty judgment — that results from a

trial court’s error in improperly excluding a prospective juror for

cause during the death-qualification stage of jury selection, we

expect a trial court to make a special effort to be apprised of and

to follow the well-established principles and protocols

pertaining to the death qualification of a capital jury. As the

present case demonstrates, an inadequate or incomplete

examination of potential jurors can have disastrous

consequences as to the validity of a judgment. The error that

occurred in this case — introducing a fatal flaw that tainted the

outcome of the penalty phase even before the jury was sworn —

underscores the need for trial courts to proceed with special care

and clarity in conducting voir dire in death penalty trials. The

circumstance that the error in this case was committed by a trial

judge with substantial experience in criminal law renders the

voir dire examination at issue all the more inexplicable and

disappointing.” (People v. Heard, supra, 31 Cal.4th at pp. 966–

967.)

Those remarks apply with full force to this case. Because

the trial court failed to develop a record sufficient to support

excusal of jurors for cause, and because the prosecution did not

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Opinion of the Court by Kruger, J.

speak up as these errors were occurring to ensure an adequate

record, the penalty phase in this case was over before it ever

began. It is in no one’s interest for a capital case to begin with

the certainty that any ensuing death verdict will have to be

reversed and the entire penalty case retried. (See People v.

Heard, supra, 31 Cal.4th at p. 968.) We emphasize what we said

in Heard, and have said many times before and since: Before a

prospective capital juror is dismissed on the basis of death

penalty views, it is imperative that the party seeking dismissal

and the trial court ensure a record adequately establishing those

views is developed. (See, e.g., People v. Buenrostro, supra, 6

Cal.5th at p. 412; People v. Covarrubias (2016) 1 Cal.5th 838,

863–866; People v. Zaragoza (2016) 1 Cal.5th 21, 37–41; People

v. Leon, supra, 61 Cal.4th at p. 592.) Jurors may not be excused

merely for opposition to the death penalty, but only for views

rendering them unable to fairly consider imposing that penalty

in accordance with their oath. The record must make manifest

that inability — not with “ ‘unmistakable clarity’ ” (Witt, supra,

469 U.S. at p. 424), to be sure, but with sufficient clarity that a

reviewing court can identify a basis for the trial court’s

conclusion that the juror actually lacked the requisite ability. In

the absence of such a record, we have no choice but to reverse

the death sentence. (Buenrostro, at pp. 415–418.)

Peterson, however, asks us to go one step further. He

argues that the errors in jury selection affected all parts of his

trial, not just the penalty phase, and rendered the results of the

jury’s guilt phase deliberations unreliable as well. He

accordingly asks that we set aside not only his sentence but the

murder convictions that preceded it. Both the United States

Supreme Court and this court have previously declined to take

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Opinion of the Court by Kruger, J.

this additional step, and Peterson offers no persuasive ground

for doing so here.

The United States Supreme Court in Witherspoon rejected

the argument that errors in death qualifying a jury necessarily

undermine its guilt phase verdict in addition to its penalty

judgment. Invoking surveys and academic studies, Witherspoon

had argued that “the kind of juror who would be unperturbed by

the prospect of sending a man to his death . . . is the kind of juror

who would too readily ignore the presumption of the defendant’s

innocence, accept the prosecution’s version of the facts, and

return a verdict of guilt,” and thus his jury was biased as to guilt

too. (Witherspoon, supra, 391 U.S. at pp. 516–517; see id. at p.

517, fns. 10, 11.) The high court was unpersuaded. While the

court considered it “self-evident” that errors in death

qualification would undermine the jury’s impartiality “in its role

as arbiter of the punishment to be imposed” (id. at p. 518),

Witherspoon’s studies failed to show that the same was true of

the jury in its different capacity as finder of fact (id. at pp. 517–

518; see id. at p. 521, fn. 20 [determination whether to impose

the death penalty “is different in kind from a finding that the

defendant committed a specified criminal offense”]). The court

explained: “We simply cannot conclude, either on the basis of

the record now before us or as a matter of judicial notice, that

the exclusion of jurors opposed to capital punishment results in

an unrepresentative jury on the issue of guilt or substantially

increases the risk of conviction.” (Id. at pp. 517–518.) Despite

a record in which “the prosecution eliminated nearly half the

venire of prospective jurors by challenging . . . any venireman

who expressed qualms about capital punishment” (id. at p. 513),

the high court refused to disturb the guilty verdict (id. at

pp. 518, 522–523, fn. 21). Our own cases have followed the same

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Opinion of the Court by Kruger, J.

path, reversing the death judgment in cases of jury-selection

error but declining to disturb the guilty verdict. (See, e.g.,

People v. Armstrong, supra, 6 Cal.5th at p. 764; People v.

Stewart, supra, 33 Cal.4th at p. 455.)

Peterson candidly acknowledges this precedent, but asks

us to distinguish it on the ground that Witherspoon and

subsequent cases considered only whether the Sixth and

Fourteenth Amendments to the United States Constitution

require a guilty verdict be set aside; Peterson argues the Eighth

Amendment compels a different result. But Peterson’s Eighth

Amendment claim “appears to be merely a restatement of [the]

Sixth Amendment claim[].” (People v. Johnson (1992) 3 Cal.4th

1183, 1213.) Though couched in terms of Eighth Amendment

reliability, as opposed to Sixth Amendment representativeness,

it depends on the identical premise — that the exclusion of

jurors generally opposed to the death penalty tilts the venire to

an unacceptable degree in favor of the prosecution on questions

of guilt as well as sentence. On the record before it, the court in

Witherspoon was unable to say that even systematic exclusion

of those opposed to the death penalty “substantially increase[d]

the risk of conviction.” (Witherspoon, supra, 391 U.S. at p. 518.)

The 1984, 1986, and 1994 studies Peterson cites do not lead to a

different conclusion. He relies on research analyzing how the

constitutionally accepted process of “death qualification” — i.e.,

the dismissal of potential jurors who would either always or

never vote for death — alters the willingness to convict. These

studies do not establish that excluding one — or even 13 —

prospective jurors, from a pool of nearly 1,500, “substantially

increase[s] the risk of error in the factfinding process.” (Beck v.

Alabama (1980) 447 U.S. 625, 632.) Nor does Peterson point to

any evidence in the record to support this claim.

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Peterson argues that even if the errors in jury selection do

not require reversal of his convictions, there were several other

errors that do command that result. We therefore turn to

whether any of these asserted errors in the guilt phase trial

requires that Peterson’s murder convictions be set aside.

B. Denial of Motion to Change Venue

Peterson was arrested and charged in Stanislaus County,

where he and Laci had lived. He moved for a change of venue,

arguing that a fair and impartial trial could not be had in

Stanislaus because of the extensive publicity the case had

received. The Stanislaus County Superior Court granted the

motion and, after considering the alternatives recommended by

the Administrative Office of the Courts,11 including Alameda,

Santa Clara, and Orange Counties, selected San Mateo County

as the best venue. It found that local media coverage and the

degree of community involvement in the case would preclude a

fair trial in Stanislaus, but any county of sufficient size outside

the Central Valley could provide a fair trial. San Mateo was

selected based on its facilities and its relative proximity

compared to Southern California, which would minimize travel

for the many Modesto-area witnesses.

Jury selection began in March 2004. In May 2004,

Peterson filed a second change of venue motion, this time

seeking transfer of the case to Los Angeles County. He argued

that examination of questionnaire answers from prospective

jurors showed, once again, that extensive pretrial publicity was

11

The Administrative Office of the Courts was the name of

a body serving the Judicial Council of California. In 2014, the

name was retired to better reflect that the office was, and is, a

subpart of the Judicial Council.

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affecting the juror pool. The trial court considered the parties’

papers and arguments and made a detailed oral ruling denying

a further venue change. Peterson contends the denial of his

second motion violated his federal constitutional right to trial by

an impartial jury (U.S. Const., 6th & 14 Amends.) and similar

state guarantees.

In a series of cases in the 1960s, the United States

Supreme Court recognized that media publicity about a criminal

trial could in some circumstances deprive the defendant of the

right to trial by an impartial jury. (Sheppard v. Maxwell (1966)

384 U.S. 333; Estes v. Texas (1965) 381 U.S. 532; Rideau v.

Louisiana (1963) 373 U.S. 723; Irvin v. Dowd (1961) 366 U.S.

717; see generally Skilling v. United States (2010) 561 U.S. 358,

378–381.) In the wake of these decisions, to ensure “the

requirement basic to our jurisprudence that every person

accused of crime is entitled to a trial by a fair and impartial jury”

(Maine v. Superior Court (1968) 68 Cal.2d 375, 384), this court

adopted a new standard for pretrial change of venue motions:

Such a motion should “ ‘be granted whenever it is determined

that because of the dissemination of potentially prejudicial

material, there is a reasonable likelihood that in the absence of

such relief, a fair trial cannot be had’ ” (id. at p. 383; see Pen.

Code, § 1033, added by Stats. 1971, ch. 1476, § 3, p. 2915

[codifying the Maine standard]).

Over time, we have elaborated on the prophylactic Maine

standard and identified a series of considerations courts must

weigh to ensure the constitutional right to a fair trial is

preserved. “The factors to be considered are the nature and

gravity of the offense, the nature and extent of the news

coverage, the size of the community, the status of the defendant

in the community, and the popularity and prominence of the

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victim.” (People v. Harris (1981) 28 Cal.3d 935, 948; accord, e.g.,

People v. Rices (2017) 4 Cal.5th 49, 72.) “On appeal, the defense

bears the burden of showing both error and prejudice. It must

establish a reasonable likelihood both that a fair trial could not

be had at the time of the motion, and that the defendant did not

actually receive a fair trial.” (People v. Smith (2015) 61 Cal.4th

18, 39; see People v. McCurdy (2014) 59 Cal.4th 1063, 1075.)

Alternatively, in rare and “exceptional cases,” a defendant may

show circumstances so “ ‘extraordinary’ ” that a court may

assume no fair trial could be had. (People v. Prince (2007) 40

Cal.4th 1179, 1216.) We accept when supported by substantial

evidence the facts a trial court finds in connection with a motion

to change venue. (Smith, at p. 39; McCurdy, at p. 1075.) As

dictated by Sheppard v. Maxwell, supra, 384 U.S. at page 362

and Maine v. Superior Court, supra, 68 Cal.2d at page 382,

however, we will independently review all the circumstances to

determine whether there was a reasonable likelihood of an

unfair trial. (Smith, at p. 39; McCurdy, at p. 1075.)

Conceding that the other factors were “largely neutral,”

Peterson rests his argument that denial of a second change in

venue was error on a single consideration, the nature and extent

of pretrial publicity. This case was the subject of massive,

worldwide media attention. Peterson asserts, and the People do

not dispute, “that the combination of print media, radio

coverage, television and cable and internet coverage made this

perhaps the most widely covered trial in American history.” The

trial judge remarked, “The only place you could send this case

probably where they wouldn’t [have] hear[d] about it — I’m not

so sure about that — would be send it to Mars, you know. That’s

the only place where you could try this case where nobody would

know anything about it. It’s been all over the world.” We also

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take as a given that much of this publicity portrayed Peterson

in a negative light. We nonetheless find no error in the trial

court’s denial of Peterson’s second change of venue motion.

Preliminarily, we reject Peterson’s argument that when

unfavorable publicity reaches the saturation level of this case,

any denial of a change of venue motion is presumptively

prejudicial and a defendant need not show an impartial jury

could not be seated. To the contrary, “ ‘it is well-settled that

pretrial publicity itself — “even pervasive, adverse publicity —

does not inevitably lead to an unfair trial.” ’ ” (People v. Prince,

supra, 40 Cal.4th at p. 1216; see Murphy v. Florida (1975) 421

U.S. 794, 799; People v. Harris, supra, 28 Cal.3d at pp. 949–950.)

Rather, a “presumption of prejudice” from excessive publicity

“attends only the extreme case” (Skilling v. United States,

supra, 561 U.S. at p. 381), one in which the “ ‘trial atmosphere

[is] utterly corrupted by press coverage’ ” (id. at p. 380).

Peterson has not shown that the atmosphere outside the

courtroom reached inside the courtroom and categorically

precluded a fair trial.

In similar cases, courts have held that a change of venue

motion may be denied if the change would be futile: “Where

pretrial publicity has been geographically widespread and

pervasive . . . , a court may deny change of venue on the sensible

ground that it would do no good.” (People v. Venegas (1994) 25

Cal.App.4th 1731, 1738.) For cases of a certain profile, it would

be “speculation to suppose the results of jury selection would

have been significantly different in any county. The media

report local trials of notorious crimes in all counties. People read

newspapers and watch television” — and, we may now add, use

the Internet — “in all counties.” (People v. Cooper (1991) 53

Cal.3d 771, 807.) Discussing the trial of members of the Charles

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Manson family, the Court of Appeal wrote: “It is patently clear

that the crimes charged, as well as the identity and the

involvement of appellants, permeated every corner of this state

with varying degrees of intensity. The ubiquity of media

coverage made any such differential one of insignificant degree.

A change of venue offered no solution to the publicity problem.

Even if venue had been changed, nothing could have prevented

the public media from swinging its attention to that place. The

magnetic pull of such notorious cases is compelling.” (People v.

Manson (1976) 61 Cal.App.3d 102, 176–177; see People v. Davis

(2009) 46 Cal.4th 539, 578–579.)

The same is true here. Precisely because this case was the

subject of such widespread media attention, it is unclear what

purpose a second change of venue would have served. The

publicity the Peterson trial generated, like the trials of O.J.

Simpson, the Manson family, and any number of other so-called

trials of the century before them, was intrinsic to the case, not

the place. This was even more true than in earlier times

because, as Peterson rightly notes, his trial followed the

explosion of cable television and the Internet as sources of

information, facilitating nationwide coverage of the case. For

these reasons, as the trial court aptly observed, “[i]t is

speculation to suppose [the] results of jury selection would be

any different anywhere else.” Media attention followed this case

from Stanislaus County to San Mateo County. Given the level

of public interest, this case would have attracted attention in

any venue in which it was held. There is no rational reason to

think coverage would have been any less in Los Angeles

County — one of the media capitals of the world — if Peterson’s

motion had been granted.

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Against this conclusion, Peterson relies on survey

statistics measuring the levels in Los Angeles County of

awareness and prejudgment of the case, but those statistics do

not support his argument. First, the surveys did not include San

Mateo, so no direct comparisons can be drawn between Los

Angeles and San Mateo. Second, the two other Bay Area

counties surveyed, Alameda and Santa Clara, generally showed

no statistically significant differences from Los Angeles,

although all three counties were statistically significantly

different from Stanislaus, where the case was originally

pending. This led Peterson’s own expert to opine, in support of

moving the case from Stanislaus, that for a fair trial the “best

three counties that are [statistically] fairly close are Los

Angeles, Alameda, and Santa Clara County.” Third, the

statistics derive from a survey taken a full year before the

second change of venue motion and do not show how

prejudgment levels would have changed if the case were

transferred to Los Angeles, and with it the national media

spotlight. (See People v. Davis, supra, 46 Cal.4th at p. 575

[“Because it is impossible to control heightened media attention

in any new venue, it also is virtually impossible to prevent the

knowledge and prejudgment rates for potential jurors living in

a new venue from increasing after the change of venue has

occurred”].)

Instead, in a high-profile case such as this one, provided a

sufficiently large pool is available — and we agree with the trial

court that San Mateo’s 700,000-plus residents provided such a

pool — the better answer is not to change venue yet again but

to rigorously vet potential jurors to screen out those tainted and

irrevocably biased by pretrial publicity, to find 12, plus

alternates, who can decide only on the evidence admitted at

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trial. Almost inevitably even those qualified for potential

service by a court may have had some prior exposure to the case,

but “[p]rominence does not necessarily produce prejudice, and

juror impartiality, we have reiterated, does not require

ignorance.” (Skilling v. United States, supra, 561 U.S. at p. 381.)

What matters is whether each prospective juror can “ ‘lay aside

his [or her] impression or opinion and render a verdict based on

the evidence presented in court.’ ” (People v. Harris, supra, 28

Cal.3d at p. 950, quoting Irvin v. Dowd, supra, 366 U.S. at

p. 723.)

The trial court here did just this. Indeed, defense counsel

himself acknowledged, “I think the court has exercised

Herculean efforts in trying to get a fair panel here.” Nearly

1,500 prospective jurors were scrutinized. (See People v.

Famalaro (2011) 52 Cal.4th 1, 30 [“The huge number of

prospective jurors initially summoned (1,200) ensured that an

ample number of unbiased prospective jurors remained after the

biased ones had been excused”].) The court observed that “[t]he

66 people we’ve qualified so far have given us [the] assurance”

that they could set aside any prior impressions or opinions and

decide the case only on the evidence, “and the court is satisfied

that that is, in fact, the case.” Ultimately, all 18 jurors and

alternates chosen to serve had indicated in their juror

questionnaires that they had not formed any opinion as to

Peterson’s guilt or innocence because they did not have enough

information to decide. The actual seated jurors thus had no

preliminary opinions on guilt — never mind preset views they

would be unable to set aside.

Peterson argues that the seated jurors’ declarations of

impartiality should be rejected based on his survey data drawn

from the venire as a whole. We agree that “the juror’s

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assurances that he [or she] is equal to this task cannot be

dispositive of the accused’s rights.” (Murphy v. Florida, supra,

421 U.S. at p. 800.) But Peterson offers no sound basis to believe

the jurors’ assurances in this case were insincere. Almost every

prospective juror had been exposed to publicity about the case,

but this is unsurprising for a case Peterson describes as the most

publicized in American history, and would have been unlikely to

change much in any other county. According to Peterson’s

review of juror questionnaires filled out before the second

motion, 43 percent of prospective jurors (426 of 998) had formed

a preliminary opinion that Peterson was guilty, and 19 percent

(190 of 998), roughly one in five, would not be able to set aside

that view. But this still means that, by the time jury selection

was complete, the parties would have had well in excess of 1,000

avowedly impartial jurors to choose from. “When, as here, there

is a ‘large, diverse pool of potential jurors, the suggestion that

12 impartial individuals could not be empanelled is hard to

sustain.’ ” (People v. Famalaro, supra, 52 Cal.4th at p. 23,

quoting Skilling v. United States, supra, 561 U.S. at p. 382.)

Our confidence in the fairness of the actual jury rests as well on

our independent review of their voir dire, during which the

parties and court carefully vetted them to ferret out bias. (See

Famalaro, at p. 31.) Peterson has not demonstrated the trial

court could not, and did not, find 12 impartial individuals. His

claim that he was denied his right to trial before a fair jury is

without merit.12

12

Irvin v. Dowd, supra, 366 U.S. 717, People v. Tidwell

(1970) 3 Cal.3d 62, and People v. Williams (1989) 48 Cal.3d 1112,

upon which Peterson relies to argue it was error to deny a

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We acknowledge Peterson’s concern was not just that the

court would be unable to find 12 unbiased jurors. Rather, it was

that they would not stay unbiased; according to defense counsel,

“the problem is that you take that panel that may be fair here,

and you stick them back in the community and you do that on a

daily basis over five months, and you’re not going to be able to

get over the kind of community passion and what I consider to

be a polluted atmosphere.” This challenge, however, is one that

would have had to be addressed in any community to which the

case was relocated, and one the trial court took appropriate

efforts to address. A second change of venue was not the answer,

and the trial court did not err in saying so.

C. Admission of Dog Scent Trailing Evidence

Before trial, the court held an Evidence Code section 402

hearing to determine whether to admit the prosecution’s

evidence of dogs trailing Laci’s scent from her home in Modesto,

in and around Peterson’s warehouse in Modesto, on highways

leaving Modesto, and at the Berkeley Marina. After extensive

testimony from and cross-examination of various dog handlers

concerning their training, as well as their dogs’ training and

past performance, the court excluded all dog scent trailing

evidence as lacking in sufficient foundation and corroboration,

change of venue, are not comparable. In Irvin, in marked

contrast to this case, eight of the 12 actual jurors thought the

defendant guilty before trial even began. (Irvin, at p. 727.) And

in both Tidwell and Williams, the small size of the venues

(Lassen and Placer Counties, respectively) and the comparative

prominence of the victims and defendants within those

communities — factors notably absent here — weighed in favor

of concluding that a change of venue would have made a

difference. (Tidwell, at pp. 72–73; Williams, at pp. 1126–1129.)

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except for evidence of scent trailing at the Berkeley Marina. The

court explained that all the dog-trailing evidence in and around

Modesto lacked sufficient independent corroboration that Laci

had ever been where dogs purported to trail her scent. The

Berkeley Marina evidence differed because there was

corroborating evidence that Laci had been present in the area —

namely, that Laci’s remains washed ashore on the edge of the

San Francisco Bay, very near the marina.

Consistent with the trial court’s ruling, dog handler Eloise

Anderson, a member of the Contra Costa County Sheriff’s

Department search and rescue team, testified at trial about

scent trailing she conducted at the Berkeley Marina with her

dog Trimble. Anderson reported to the marina with Trimble on

December 28, 2002, four days after Laci’s disappearance.

Anderson was provided a glasses case containing a pair of Laci’s

sunglasses and asked to work with her dog to determine

whether any trail of Laci’s scent could be detected. The marina

harbor had two separate access points where someone might

enter, so Anderson had Trimble check each entry point.

Wearing rubber gloves to conceal her own scent, Anderson

opened the glasses case to expose the sunglasses inside,

presented the case with the sunglasses to Trimble, and gave a

trailing command. In the first location, Trimble responded with

a “no scent trail” signal. In the second location, Trimble “lined

out,” pulling her harness line taut, with level head, and taking

Anderson from an area near the parking lot down one of the

marina piers to a pylon on the pier where a boat could have been

tied, then giving Anderson an “end of trail” signal.

Peterson argues admission of this evidence of dog trailing

at the Berkeley Marina was error because the trial court failed

to require a hearing under People v. Kelly (1976) 17 Cal.3d 24

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(Kelly), and the prosecution failed to establish the legally

required foundation. We disagree.

When admission of expert testimony relating the use of

novel scientific methods or techniques is at issue, the proponent

of the evidence must demonstrate the technique’s reliability

through testimony from an expert qualified to opine on the

subject. The technique’s reliability, in turn, depends on a

showing that it has achieved general acceptance among

practitioners in the relevant field. Finally, the proponent of the

evidence must show any procedures necessary to ensure the

technique’s validity were properly followed in the given case.

(Kelly, supra, 17 Cal.3d at p. 30.) The purpose of these threshold

requirements — commonly referred to as the Kelly test — is to

protect against the risk of credulous juries attributing to

evidence cloaked in scientific terminology an aura of

infallibility. (Id. at pp. 31–32.)

Not every subject of expert testimony needs to satisfy the

Kelly test. Courts determining whether Kelly applies must

consider, first, whether the technique at issue is novel, because

Kelly “ ‘only applies to that limited class of expert testimony

which is based, in whole or part, on a technique, process, or

theory which is new to science and, even more so, the law.’ ”

(People v. Jackson (2016) 1 Cal.5th 269, 316 (Jackson).) Second,

courts should consider whether the technique is one whose

reliability would be difficult for laypersons to evaluate. A “Kelly

hearing may be warranted when ‘the unproven technique or

procedure appears in both name and description to provide some

definitive truth which the expert need only accurately recognize

and relay to the jury.’ ” (Jackson, at p. 316.) Conversely, no

Kelly hearing is needed when “[j]urors are capable of

understanding and evaluating” the reliability of expert

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Opinion of the Court by Kruger, J.

testimony based in whole or in part on the novel technique.

(Jackson, at p. 317.)

Several decades ago, in People v. Craig (1978) 86

Cal.App.3d 905 (Craig), addressing an issue then of first

impression in California, the Court of Appeal concluded no Kelly

hearing was needed before introducing dog-trailing evidence.

The court explained that dog trailing does not involve

standardized techniques and inanimate, fungible instruments

whose accepted use in the scientific community may be

established, but individual dogs, whose “ability and reliability

[should] be shown on a case-by-case basis.” (Craig, at p. 915.)

As such, Kelly does not apply; the evidence is admissible if

proper foundation is laid concerning the present ability of a

particular well-trained dog to trail a human. This “is a fact

which, like other facts, may be proven by expert testimony.”

(Ibid.)

The Court of Appeal in People v. Malgren (1983) 139

Cal.App.3d 234 (Malgren) elaborated on the foundation

necessary to introduce dog-trailing evidence. Drawing from the

analyses of sister state courts that had wrestled with the same

problem, the court identified five points a proponent must

establish: “(1) the dog’s handler was qualified by training and

experience to use the dog; (2) the dog was adequately trained in

tracking humans; (3) the dog has been found to be reliable in

tracking humans; (4) the dog was placed on the track where

circumstances indicated the guilty party to have been; and

(5) the trail had not become stale or contaminated.” (Id. at

p. 238, disapproved in part by Jackson, supra, 1 Cal.5th at

p. 325 [last factor duplicative; see discussion, post].)

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When this court first addressed these issues in Jackson,

supra, 1 Cal.5th 269, we endorsed the general approach of Craig

and Malgren. We agreed that unlike the sorts of scientific

evidence a juror might uncritically accept, for which a threshold

Kelly hearing should be held, “[s]cent trailing evidence is not so

foreign to everyday experience that it would be unusually

difficult for jurors to evaluate. Jurors are capable of

understanding and evaluating testimony about a particular

dog’s sensory perceptions, its training, its reliability, the

experience and technique of its handler, and its performance in

scent trailing” in a given case. (Jackson, at p. 317.) We thus

approved the general admissibility of “[e]vidence grounded in

the ability of particular dogs to perform scent trailing on

command . . . so long as a proper foundation is laid.” (Id. at

p. 320.)

In discussing the necessary foundation, we adopted the

Malgren factors with one modification. A proponent must

establish as background qualifications the adequacy of the

handler’s and dog’s training and supply evidence of the dog’s

reliability in trailing humans. (Jackson, supra, 1 Cal.5th at

pp. 321–322.) The party must also show the adequacy of the

manner in which the dog was given a scent to trail, whether (as

in Craig and Malgren) by being allowed to sniff the beginning of

a known trail or (as in Jackson) by being “presented with a scent

article” and then asked to smell for a corresponding trail of the

same scent. (Jackson, at p. 322.) We also approved the

corroboration requirement established in Craig, Malgren, and

People v. Gonzales (1990) 218 Cal.App.3d 403, 409 (Gonzales) —

the need for some independent evidence tending to confirm that

a person found at the end of the trail the dog followed was indeed

the person who left the scent trail and supplied the initial scent.

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Opinion of the Court by Kruger, J.

(Jackson, at p. 321.) We concluded the remaining Malgren

condition for admissibility — evidence the source of the initial

scent had not become stale or contaminated — was essentially

duplicative of the other elements and thus need not be shown

independently. “If a well-qualified handler trains a dog who has

reliably trailed human scent and is well trained in ignoring or

forgetting past smells and in indicating negative trails, then the

dog will not trail if the scent on the scent item is stale or

nonexistent, or if there is no trail that matches the scent on the

scent item.” (Jackson, at p. 325.) Thus, evidence of the

remaining Malgren requirements ordinarily will suffice to

support admission of dog-trailing evidence. (See People v.

Westerfield (2019) 6 Cal.5th 632, 706.)

As in Jackson, we conclude the trial court did not err in

declining to subject the dog-trailing evidence to the threshold

Kelly test. The nature of the dog-trailing technique at issue here

is not meaningfully different from the technique at issue in

Jackson, which we concluded was not subject to Kelly. In

Jackson, on one occasion, a trained dog was given a gauze pad

infused with scent from a fresh shoe print left outside a victim’s

house and then taken to a lobby through which a suspect had

passed. The dog was able to trail from the lobby to an interview

room where the suspect was sitting, whereupon the dog alerted

to the suspect. (Jackson, supra, 1 Cal.5th at pp. 308–309.) On

a second occasion, a dog was given a gauze pad infused with

scent from an envelope left on a different victim’s bed and

believed to have been handled by the perpetrator. The dog was

again asked to seek out and follow any matching trail, and

trailed from a point outside the police station to a locker room

inside the station, where the suspect was sitting, and again

alerted to the suspect. (Id. at p. 309.) The essential task the dog

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PEOPLE v. PETERSON

Opinion of the Court by Kruger, J.

was asked to perform was to “follow any human scent that she

could pick up from the envelope.” (Id. at p. 320.) Here, Trimble’s

task was not fundamentally different in nature: She was

presented with Laci’s sunglasses and then directed to smell for

trails of the same human scent, if any, at the Berkeley Marina.

This was not a novel technique; indeed, Anderson testified that

teaching a dog to scent off an object and then seek a

corresponding trail is a routine part of training dogs to trail

humans. Nor was it a technique whose fallibility would have

been opaque to laypersons. Under Jackson, no Kelly hearing

was necessary before the evidence was admitted, provided that

the requisite foundational requirements were satisfied.

Turning to that necessary foundation, Peterson argues we

should supplement the requirements set out in Jackson with

additional requirements derived from the Court of Appeal’s

decisions in People v. Willis (2004) 115 Cal.App.4th 379 (Willis)

and People v. Mitchell (2003) 110 Cal.App.4th 772, 790–794

(Mitchell). We declined to impose these requirements in

Jackson, and there is no reason for a different result here.

(Jackson, supra, 1 Cal.5th at pp. 319–320.)

In Willis, the dog was not asked to smell for a scent trail,

but instead was exposed to a scent and then “watched to see if

the dog ‘show[ed] interest’ in various locales frequented by the

defendant.” (Willis, supra, 115 Cal.App.4th at p. 386.) This sort

of scent identification, the court held, should be admissible only

upon foundation concerning such matters as “how long scent

remains on an object or at a location” and “whether every person

has a scent that is so unique that it provides an accurate basis

for scent identification.” (Ibid., citing Mitchell, supra, 110

Cal.App.4th at pp. 791–792.) In Mitchell, on which Willis relied,

a dog had been given pads with scent from murder shell casings

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Opinion of the Court by Kruger, J.

and the victim’s shirt and a lineup of pads with scents from

various people, including the defendants. The dog alerted to a

match with pads containing one defendant’s scent, but not the

other’s. (Mitchell, at pp. 780–781.) The Court of Appeal

distinguished between scent trailing, which was established as

admissible without any Kelly hearing, and a scent lineup of the

sort performed in Mitchell. (Mitchell, at p. 790.) Such a lineup,

the court reasoned, did not have the kind of centuries-long

lineage that scent trailing does, and thus ought to be supported

by additional foundation establishing the uniqueness of human

scents and their persistence and rate of degradation. (Id. at

pp. 793–794.)

Here, the dog-trailing evidence admitted at trial did not

resemble either the open-ended identification at issue in Willis

or the scent lineup at issue in Mitchell. Trimble was not asked

to match a scent to a general location the target may have

frequented at unspecified times in the past, nor was she asked

to distinguish among multiple people or objects on the basis of

their scents. Rather, Trimble was asked to seek out and follow

a trail, if any could be found, based on a given scent. Jackson

rejected the need for additional foundation tied to scent

identification before introducing evidence of a dog’s performance

of a very similar task. (Jackson, supra, 1 Cal.5th at pp. 319–

320.) No more foundation than that required by Malgren and

Jackson for analogous tasks was necessary here.

Again, under the Malgren test, as modified in Jackson, the

prosecution was required to show that Anderson was sufficiently

trained, that Trimble was sufficiently trained and reliable in

tracking humans, that Trimble was properly given an initial

scent to trail, and that some evidence tended to corroborate

Trimble’s trailing. We review the trial court’s determination

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that adequate foundation was laid for abuse of discretion.

(Jackson, supra, 1 Cal.5th at p. 321.) If substantial evidence

supports each foundational element, the decision to admit dog-

trailing evidence will be upheld. (Ibid.; Craig, supra, 86

Cal.App.3d at p. 917.)

Anderson testified about her experience over more than

two decades training dogs. She described her dog Trimble’s

certificates and training, which included certification in trailing

from the California Rescue Dog Association and repeated

seminars and training exercises over a period of years leading

up to her use in trailing Laci’s scent in December 2002.

Trimble’s training included out-of-state sessions to give her

experience trailing under varied environmental factors, terrain,

and weather conditions. Anderson described many of Trimble’s

successful human scent trailings, including numerous instances

of trailing noncontact trails13 and successfully following trails

four days old or even older.14 Anderson opined that Trimble was

reliable in trailing humans. Based on the foregoing evidence,

which was substantial, the trial court made specific findings

13

A noncontact trail is one left by a person not in contact

with the ground, as on a bicycle or in a vehicle.

14

For example, in a November 1999 exercise, Trimble

successfully trailed a person who had left a trail largely on

asphalt, which retains scent more poorly than vegetation. The

trail was five days old and there had been intervening

rainstorms. In a December 2001 exercise, Trimble successfully

followed a four-day-old noncontact trail left by a bicyclist riding

the 30 miles from Walnut Creek to Dublin. Given the length of

the trail, it was not physically possible for Trimble to cover the

entire distance, so at various points she was driven from one

section of the trail to a later section, but she was able to relocate

and follow the bicyclist’s scent each time.

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that Anderson and Trimble were adequately trained and

Trimble was reliable at tracking humans.

The fourth Malgren element, the adequacy of the fashion

in which the dog was given a scent to trail, was established with

testimony that Trimble was exposed to a scent object of Laci’s,

her sunglasses. (See Jackson, supra, 1 Cal.5th at p. 322.) This

case is thus unlike Willis, where the dog was given an initial

scent from a matchbook but the prosecution failed to present any

“proof that [the target] ever touched the matchbook from which

a scent was collected.” (Willis, supra, 115 Cal.App.4th at p. 386.)

Finally, the court found corroboration of Trimble’s trailing —

reason to think her identification of Laci’s scent along a path

down to the water was accurate — from evidence that Laci’s

body would, some months later, wash ashore not far from the

marina. That evidence, and its tendency to give credence to

Trimble’s trailing, are beyond reasonable dispute.15 Substantial

evidence supports the court’s determination that the Berkeley

Marina dog-trailing evidence was admissible.

15

In his reply brief, Peterson challenges the trial court’s

ruling on the ground that the prosecution presented no other

evidence proving Laci was at the Berkeley Marina. This is true,

but it was not an unreasonable inference based on the evidence

that was presented. Laci disappeared in Modesto, California, a

90-mile drive inland from Berkeley; her remains washed ashore

in the San Francisco Bay, just two to two and one-half miles

from the marina; and the marina was one of the closest access

points to the bay from Modesto. These facts offer some reason

to believe Laci, or her body, was taken to the San Francisco Bay

by way of the marina. This is to say nothing of the other

evidence that Peterson was responsible for Laci’s disappearance

and, by his own admission, was at the Berkeley Marina on

December 24. The trial court did not err in holding that the

corroboration element had been satisfied.

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Peterson does not contest the sufficiency of this testimony

to establish that Anderson and Trimble had sufficient training

in trailing scents and that Trimble had shown herself generally

capable of identifying and following human scents. He argues,

however, that the prosecution failed to establish specific

essential qualifications for both Anderson and Trimble: that

Anderson had specialized training to avoid certain handler

behaviors, and that Trimble had demonstrated success in

particular conditions mirroring those at the Berkeley Marina.

Regarding Anderson’s training, Peterson argues that

Anderson never testified her training included specific

instruction on how to avoid cueing dogs to go in a desired,

predetermined direction when trailing. Neither we nor the

Courts of Appeal have ever held such specific testimony a

mandatory prerequisite. (Cf. Florida v. Harris (2013) 568 U.S.

237, 244 [in the context of warrantless searches challenged

under the 4th Amend., the reliability of a drug-sniffing dog

should be evaluated under the totality of the circumstances,

rather than according to a “strict evidentiary checklist”].)16 Nor

did Peterson argue to the trial court that this more specific

16

Peterson argues that other jurisdictions require testimony

concerning cue avoidance, but review of the published case law

he relies on and subsequent decisions belies the assertion.

Although some of the cases he cites have referred to such

testimony, or the absence thereof, in passing, none holds that

such testimony is necessary before dog-trailing evidence may be

admitted. (See U.S. v. Trayer (D.C. Cir. 1990) 898 F.2d 805, 809;

U.S. v. One Million, Thirty-Two Thousand, Nine Hundred

Eighty Dollars in U.S. Currency ($1,032,980.00) (N.D.Ohio

2012) 855 F.Supp.2d 678, 699; Harris v. State (Fla. 2011) 71

So.3d 756, 768–769, revd. sub nom. Florida v. Harris, supra, 568

U.S. 237; State v. Helzer (2011) 350 Or. 153, 158–159 [252 P.3d

288]; State v. England (Tenn. 2000) 19 S.W.3d 762, 768–769.)

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foundation should have been supplied, at a time when the

prosecution would have had the opportunity to rectify any

perceived omission. It is therefore too late to raise the issue

now. (See Florida v. Harris, at pp. 248–249 [failure to voice in

the trial court doubts about the sufficiency of dog’s training bars

raising those concerns for the first time on appeal].)

In any event, the record does demonstrate that Anderson

was aware of the dangers of trainer cueing and sought to avoid

them. She testified that she did everything possible to remain

neutral and trained Trimble in specific ways to ignore her as

much as possible, and that their joint training included

successfully working numerous blind trails where neither knew

in advance where the subject had gone. During cross-

examination of prosecution witnesses, in the defense case, and

in closing argument, Peterson was free to address whether

Trimble’s performance at the marina was tainted by trainer

cueing. (See Florida v. Harris, supra, 568 U.S. at pp. 246–247

[proof of certification or successful completion of a training

program supports presumption of dog’s reliability, but subject to

cross-examination and introduction of conflicting evidence by

the defendant]; Jackson, supra, 1 Cal.5th at p. 297 [defendant

introduced expert testimony that particular dog-trailing

evidence was unreliable because the procedure used permitted

inadvertent cueing].) He chose not to. Of course, had Peterson

done so, the prosecution could have argued that if Trimble was

merely responding to her handler’s subconscious desire to find a

path, she would have done so in the first place they checked,

rather than giving her handler a “no trail” signal. Ultimately,

whether cueing might have affected Trimble’s performance is a

matter the jury could consider in deciding what weight to give

it, but the absence of testimony about specific training designed

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to avoid cueing did not render the evidence categorically

inadmissible.

Peterson next argues that the prosecution was required to

present foundation that Trimble was reliable in the specific

conditions under which she performed scent trailing at the

marina. We have never required, and see no basis for

demanding, that the proponent of dog-trailing evidence

demonstrate past performance in conditions that are identical

to the case at hand. All the training and experience a dog

receives has relevance in assessing the dog’s reliability in

trailing humans. (Jackson, supra, 1 Cal.5th at p. 322 [trial court

finding of reliability supported by generalized training]; see

Florida v. Harris, supra, 568 U.S. at pp. 244–247 [totality of the

circumstances relevant to assessing drug-sniffing dog’s

reliability].) As with the cueing issue just addressed, a

defendant is free to introduce evidence, cross-examine

witnesses, and present argument that aspects of the trailing

environment made the detection of a scent trail more fraught

and subject to error. But the failure of a particular dog to have

trailed in circumstances precisely mirroring those in a given

case does not preclude the jury from considering trailing

evidence.

Nor, in any event, do the specific features of the marina

trailing undermine the soundness of the trial court’s

determination that the prosecution’s foundation was adequate.

Peterson emphasizes that the trailing involved a “marine”

environment. Trimble was not asked to trail at sea; she was

asked to trail in a field, parking lot, and dock that were adjacent

to a body of water. Peterson offered no evidence that trailing on

land in an area adjacent to a body of water poses significant

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difficulties.17 Peterson also stresses the noncontact nature of

the trail, but Anderson testified at length about Trimble’s many

successful trailing exercises involving noncontact trails.

Lastly, under the prosecution’s theory, Laci’s body was

covered by a tarp when she was in the marina, and so Peterson

highlights the fact that Trimble’s one undisputed failure in a

training exercise had involved an enclosed target. But the

prosecution presented evidence that on a different occasion,

Trimble had previously successfully trailed an enclosed target,

following a trail generated by a subject in the closed trunk of a

car.18

Of course, Peterson was also entitled to try to undercut

Anderson’s testimony by pointing to Trimble’s track record in

trailing enclosed targets, and he did just that: He cross-

examined Anderson about Trimble’s failure, as well as the more

general difficulties with following a trail left by someone in a

closed vehicle. The jury was then specifically instructed that in

weighing testimony concerning Trimble’s performance, it could

consider “any other factor that could affect the accuracy of the

dog tracking evidence.” The particular circumstances involved

in the trailing exercise here may have made Trimble’s task more

or less difficult, but they did not alter the fundamental nature

of the task — which, again, is the type of task dogs have

performed for centuries. Those circumstances were thus

17

Indeed, Christopher Boyer, the head of the Contra Costa

County Sheriff’s Department’s search and rescue team, testified

that humidity enhances the ability of scent to adhere to surfaces

and may make it easier for dogs to trail.

18

A third test Peterson cites, from October 2002, was the

subject of vigorous debate as to whether Trimble succeeded and

whether the test was even an enclosed-target test.

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relevant to the weight the jury might accord this evidence, but

not its admissibility.

Finally, Peterson argues that the dog-trailing evidence

should have been excluded because Anderson failed to perform

a “missing member” test on Laci’s sunglasses. Anderson

explained that when a scenting object has two “equally intense”

scents on it, a handler may present the object and then have the

dog smell the target she does not want the dog to trail. Trailing

dogs are then taught to seek out a trail that matches the

remaining scent — the person that is missing, i.e., the “missing

member.” Peterson suggests it is possible that he may have

touched Laci’s sunglasses at some point in the past. He argues

Anderson therefore should have performed a missing member

check to eliminate the possibility that Trimble was following

Peterson’s own scent from when he was, concededly, at the

Berkeley Marina a few days earlier.

There are two difficulties with this argument. First,

Anderson testified, and Peterson does not dispute, that trailing

dogs are trained to follow the freshest, most recent scent on a

particular object. There is no evidence in the record that

Peterson handled Laci’s sunglasses so recently that his scent

would be equally fresh and risk confusing Trimble. Indeed,

there is nothing in the record to show Peterson handled the

sunglasses at all. The most Peterson can point to is hearsay,

inadmissible for its truth, that Peterson had handled Laci’s

purse at some unspecified time in the past. Second, and in any

event, conducting a missing member test is not a foundational

requirement for admission of dog-trailing evidence. Peterson

does not dispute that Laci handled her own sunglasses, and that

Trimble was then given the sunglasses as a scent object before

attempting to find a trail. Given this, the prosecution

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adequately established foundation for the fourth Malgren

factor — “that the dog was presented with a scent article that

the jury could infer was handled by” the target. (Jackson, supra,

1 Cal.5th at p. 322.) Whether Peterson also handled the

sunglasses so recently Trimble became confused was a matter

he could, and did, argue to the jury. (See id. at pp. 325–326

[even when foundation established, defendant free to cross-

examine witnesses and present rebuttal evidence].) But

Peterson fails to establish that the evidence rested on an

inadequate foundation to support its admission.

For the same reasons, Peterson fails to establish that

admission of the evidence violated his federal constitutional

right to a reliable guilt determination in a capital case. (U.S.

Const., 8th & 14th Amends.) The dog-trailing evidence was not,

as defendant claims, inherently unreliable; it rested on a solid

foundation and could fairly be considered by the jury alongside

whatever arguments against its significance and accuracy

Peterson chose to muster.

While we see no error in the admission of Trimble’s scent

trailing, we also see no reasonable possibility that the jury

would have returned a different verdict had the scent trailing

evidence been excluded. Peterson contends that the evidence

was crucial because the prosecution relied heavily on it. But the

prosecutor devoted only a few sentences to the subject in the

course of closing and rebuttal arguments that stretched for 150

pages of transcript. If credited by the jury, the trailing evidence

would have shown Laci was at the Berkeley Marina in late

December 2002. The jury, however, already knew Laci’s body

had been deposited in the San Francisco Bay months before she

washed ashore in April 2003, and there were a limited number

of access points, among which the Berkeley Marina was closest

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to where she was found. The trailing evidence did not add much

beyond what could already be inferred from other evidence. It

also did not rule out the defense’s theory “that somebody [else]

abducted her” and then disposed of her in the bay. And the

trailing testimony aside, there was considerable other

circumstantial evidence incriminating Peterson, from the

simple fact that Laci’s and Conner’s bodies washed ashore 90

miles from their home but within sight of where Peterson

admitted he went fishing the day they disappeared; to the

research Peterson did on bay currents in the weeks preceding

her disappearance and the fishing boat he bought but mentioned

to no one; to Peterson’s inability to explain what he was fishing

for in the middle of the day; to his repeated subsequent

surreptitious trips to the marina in the weeks after her

disappearance; to the many steps he took in the weeks after she

went missing — selling her car, exploring sale of the house,

turning the nursery into a storage room — that indicated he

already knew Laci and Conner were never coming back. Even

under the most stringent harmlessness standard, for federal

constitutional error (Chapman v. California (1967) 386 U.S. 18,

24), it is clear beyond a reasonable doubt exclusion of the limited

dog-trailing evidence admitted by the trial court would have had

no impact on the jury’s determination that Peterson was guilty.

D. Instructions on Dog Scent Trailing Evidence

1. CALJIC No. 2.16 Does Not Provide an Alternate

Theory of First Degree Murder

The jury was instructed with a modified version of

CALJIC No. 2.16, which provided guidance concerning how to

evaluate the dog-trailing evidence that had been introduced.

Peterson argues that the instruction permitted the jury to find

him guilty of first degree murder, without proof of malice, based

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solely on the dog-trailing evidence once its accuracy was

corroborated. This is incorrect.

Because the dog-trailing evidence involved following the

scent of a missing victim, not a suspect, the court slightly

modified CALJIC No. 2.16. The jury was instructed: “Evidence

of dog tracking of the victim has been received for your

consideration. This evidence is not, by itself, sufficient to permit

an inference that the defendant is guilty of the crime of murder.

Before guilt may be inferred, there must be other evidence that

supports the accuracy of the dog tracking evidence. The

evidence can be direct or circumstantial, and must support the

accuracy of the dog tracking evidence. [¶] In determining the

weight to give to dog tracking evidence, you should consider: [¶]

One, whether or not the handler was qualified by training and

experience to use the dog; [¶] Two, whether or not the dog was

adequately trained in tracking humans; [¶] Three, whether or

not the dog has been found reliable in tracking humans; [¶]

Four, whether the dog was placed on the track where

circumstances have shown the victim to have been; [¶] Five,

whether or not the trail has become stale or contaminated by

the environment, weather, or any other factor; [¶] And, six, any

other factor that could affect the accuracy of the dog tracking

evidence.”

Peterson focuses specifically on one sentence in the

instruction: “Before guilt may be inferred, there must be other

evidence that supports the accuracy of the dog tracking

evidence.” As we have previously noted (see Jackson, supra, 1

Cal.5th at p. 336), this portion of the instruction restates the law

as set forth in a 1990 Court of Appeal decision, Gonzales, supra,

218 Cal.App.3d 403. Like other California courts that had

previously addressed the issue (see Malgren, supra, 139

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Cal.App.3d at pp. 241–242; Craig, supra, 86 Cal.App.3d at

p. 918), Gonzales held that dog-trailing evidence requires

corroboration, and it explained why. Corroboration is necessary

not because a dog might be untrustworthy — the reason

corroboration is required in the case of accomplice testimony —

but because it might be inaccurate. (Gonzales, at pp. 410–412.)

Without the ability to question a dog, we cannot be as sure that

on a given occasion the dog correctly identified a starting scent

and thereafter correctly located and followed a trail of that scent

to a given destination. (Id. at pp. 412–413.) Uncertainty as to

the underlying accuracy of the trailing undermines the

reliability of any inferences one might otherwise draw from the

trailing evidence. (See id. at p. 412.) The corroboration

requirement mitigates that uncertainty, ensuring there are

“other circumstances supporting the accuracy of the inferences

drawn from the dog-tracking evidence.” (Id. at pp. 413–414; see

id. at p. 414 [“corroborating evidence . . . allows assurance that

the inferences we draw from any of the various pieces of

circumstantial evidence, including the dog-tracking evidence,

are correct”].)

As relevant here, however, Gonzales made clear that

corroboration does not automatically permit a jury to leap from

acceptance of the dog’s accuracy to the ultimate conclusion of

guilt. The inferences each bit of circumstantial evidence may

support are but an intermediate step in the process. (See

Gonzales, supra, 218 Cal.App.3d at p. 414 [“As with any

circumstantial reasoning process, the ultimate conclusion is

predicated upon many inferences that are drawn” from various

pieces of circumstantial evidence, including dog trailing

evidence].) Without corroboration, the accuracy of dog trail

evidence is too uncertain to support any inferences; with

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corroboration, that evidence may support one or more

inferences, which in turn may be relied upon by a jury to reason

its way to a final conclusion concerning guilt.

Although Peterson contends otherwise, CALJIC No. 2.16

does correctly capture these principles. (See Jackson, supra, 1

Cal.5th at p. 336.) According to the portion in dispute here, dog

trailing “evidence is not, by itself, sufficient to permit an

inference that the defendant is guilty of the crime of murder.

Before guilt may be inferred, there must be other evidence that

supports the accuracy of the dog tracking evidence. The

evidence can be direct or circumstantial, and must support the

accuracy of the dog tracking evidence.” In other words,

independent corroborating evidence of the dog’s accuracy on the

occasion in question is required foundation before any inference

pointing toward guilt may be drawn. The instruction is not

reasonably read, as Peterson suggests, to equate an inference of

guilt based on a single piece of evidence with the ultimate

conclusion that the defendant is guilty beyond a reasonable

doubt. (See Gonzales, supra, 218 Cal.App.3d at p. 414.)

We see no reasonable likelihood the jury was confused on

this point. Here, the trial court concluded the Berkeley Marina

dog-trailing evidence could go to the jury because there was

corroboration that Trimble had accurately extracted Laci’s scent

from her sunglasses and then trailed that scent to the end of a

pier in the marina — specifically, the fact Laci’s body was later

found on the shores of the San Francisco Bay, at a point a

relatively short distance from the marina. If the jury credited

Trimble as accurate, it could then draw inferences pointing

toward Peterson’s guilt — such as that, within days of the

December 28, 2002, trailing, Laci (whether then alive or dead)

was at a pier in the marina where Peterson admitted he had

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been. But as the remainder of the jury instructions made clear,

the ultimate conclusion that Peterson had committed

premeditated murder would require far more. Moments after

instructing the jury with CALJIC No. 2.16, the court gave the

jury complete, detailed instructions reminding it that a guilty

verdict required every element of a charged crime be proved

beyond a reasonable doubt, and spelling out each element that

must be shown to prove first degree murder. Reasonably

understood, CALJIC No. 2.16 did not supplant these

instructions or suggest the jury could bypass considering

whether each and every element had been proven beyond a

reasonable doubt based solely on the dog-trailing evidence.

2. CALJIC No. 2.16 Did Not Violate Any Right to

Balanced Instructions

Peterson argues that the court’s dog-trailing evidence

instruction was flawed in a second way: It referred to the

inculpatory value of dog-trailing evidence without also alluding

to its potential exculpatory value. In support of the argument,

he emphasizes that the prosecution’s evidence was not the only

dog-trailing evidence introduced at trial. Peterson presented

evidence that on December 28, 2002, the same day Trimble

trailed Laci’s scent at the Berkeley Marina, a different dog, T.J.,

was unable to trail Laci’s scent at the marina. Peterson

contends the trial court’s dog-trailing instruction was unfairly

one-sided in that it told the jury about the circumstances under

which the dog-trailing evidence could be used to convict, without

also mentioning that the evidence could be used to support

acquittal. We are unpersuaded.

Peterson’s argument rests on an analogy to Cool v. United

States (1972) 409 U.S. 100 (Cool). There, an alleged accomplice

of the defendant gave exculpatory testimony. (Id. at p. 103,

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fn. 4.) Despite the exculpatory character of the evidence, the

court instructed the jury that it could rely on the evidence to

convict, never mentioning that the jury could also rely on the

evidence to acquit: “ ‘I further instruct you that testimony of an

accomplice may alone and uncorroborated support your verdict

of guilty of the charges in the Indictment if believed by you to

prove beyond a reasonable doubt the essential elements of the

charges in the Indictment against the defendants.’ ” (Ibid.) The

Supreme Court concluded this instruction required reversal:

“[E]ven if it is assumed that [the alleged accomplice’s] testimony

was to some extent inculpatory, the instruction was still

fundamentally unfair in that it told the jury that it could convict

solely on the basis of accomplice testimony without telling it that

it could acquit on this basis.” (Ibid.) Peterson contends that

here, as in Cool, due process required an instruction that

explicitly informed the jury it could acquit on the basis of dog-

trailing evidence.

The analogy to Cool fails for several reasons. First, as just

discussed, the instruction did not tell the jury it could convict

based on the dog-trailing evidence alone. Rather, it told the jury

that such evidence, if (and only if) corroborated, could be used to

support an inference of guilt. An inference is not the same as a

conclusion that each element has been shown beyond a

reasonable doubt (see ante, at pp. 60–62), and so the instruction

here did not replicate the defect in Cool: It did not put a thumb

on the scale of the jury’s deliberations by informing them they

could return a guilty verdict based entirely on one piece of the

prosecution’s evidence. It instead placed limits on the

circumstances in which the jury could consider the prosecution’s

dog-trailing evidence, along with other evidence, as supporting

a conclusion of guilt.

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Second, it would have made no sense to impose similar

limits on the defense’s dog-trailing evidence; the dog the defense

pointed to did not find any trail, so there was no trailing

evidence that would require corroboration. And, of course, no

limiting instruction was necessary to allow the defense to use its

dog-trailing evidence for the purpose it desired: that is, as

reason for the jury not to give the prosecution’s dog-trailing

evidence much weight. The defense could, and did, argue that

T.J.’s failure to find a trail on December 28 pointed to Trimble

having been mistaken.

Finally, and in any event, the dog-trailing evidence here

was of substantially less moment in the context of the overall

case than the accomplice testimony in Cool. There, the

defendant “relied primarily on the testimony of” the alleged

accomplice. (Cool, supra, 409 U.S. at p. 101.) The

“Government’s position clearly depended upon its ability to

discredit [the alleged accomplice], since his testimony was

completely exculpatory.” (Ibid.) In such a context, an

instruction that told the jury that that testimony could be used

by itself to convict, but not to acquit, rose to the level of a due

process violation and warranted reversal of the entire

conviction. Here, in contrast, the lone dog-trailing witness

called by the defense testified for a few transcript pages, during

the course of a guilt phase trial that lasted more than five

months. The failure of the modified version of CALJIC No. 2.16

to tell the jury explicitly that it could acquit based on that scant

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absence-of-trailing evidence did not give rise to any comparable

due process violation.19

E. Admission of Expert Testimony Concerning the

Trajectory of Conner’s Body in the San

Francisco Bay

Dr. Cheng, a senior research hydrologist for the United

States Geological Survey, was called as an expert witness by the

prosecution. Dr. Cheng testified to his training, publications,

and experience analyzing fluid dynamics, with a special focus on

the San Francisco Bay. The trial court accepted him as an

expert hydrologist qualified to testify about the movement of

water in the bay and related topics. Dr. Cheng then described

two analyses he did for the Modesto Police Department. In

February 2003, while Laci was still missing, Dr. Cheng

analyzed where she might most likely be found based on an

assumption given him by the police that Laci’s body had been

placed in the bay in a particular area. In May 2003, after Laci’s

and Conner’s bodies were found, Dr. Cheng performed a second

analysis to supply his best estimate concerning where they

might have originated, and thus where divers should search for

19

Peterson makes one other argument — that the dog-

trailing evidence immediately followed a court instruction on

motive that allowed the jury to consider the presence of a motive

as weighing in favor of guilt and the absence of a motive as

weighing in favor of acquittal, and a reasonable juror would

have inferred from this sequence that by negative inference it

was not permitted to consider dog-trailing evidence as

supporting acquittal. The motive instruction actually came

after the dog-trailing evidence instruction, and, in any event, we

do not read the dog-trailing instruction as reasonably

susceptible to the understanding that jurors could not consider

such evidence as supporting acquittal.

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missing body parts and any weights or other evidence.

Dr. Cheng offered his opinion that a particular region near

Brooks Island represented the most likely starting point for

Conner, but was unable to estimate any most likely origin for

Laci.

There is no dispute that Dr. Cheng’s training and

experience qualified him as an expert in the area of fluid

dynamics and, specifically, the flow of the waters of the San

Francisco Bay. Defense counsel conceded Dr. Cheng was

qualified to give expert testimony on hydrology. But during the

Evidence Code section 402 hearing that preceded Dr. Cheng’s

testimony, Peterson asked the court to require that foundation

for Dr. Cheng’s testimony be laid under Kelly, supra, 17 Cal.3d

24. The court denied the request. Peterson now contends

Dr. Cheng’s opinions as to the movement of the victims’ bodies

in the bay were inadmissible. We review the decision to admit

the expert testimony for abuse of discretion. (People v. Banks

(2014) 59 Cal.4th 1113, 1190.) We conclude the court did not

err.

As discussed earlier, Kelly imposes certain preconditions

on the admission of evidence derived from a novel scientific

technique or procedure. The additional scrutiny “is justified

because ‘[l]ay jurors tend to give considerable weight to

“scientific” evidence when presented by “experts” with

impressive credentials. We have acknowledged the existence of

a “. . . misleading aura of certainty which often envelops a new

scientific process, obscuring its currently experimental

nature.” ’ ” (People v. Jones, supra, 57 Cal.4th at p. 952, quoting

Kelly, supra, 17 Cal.3d at pp. 31–32.)

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But in most cases no similar caution is required before a

jury considers expert opinion testimony. Unlike results

“produced by a machine,” to which jurors may “ascribe an

inordinately high degree of certainty,” jurors presented with the

personal opinion of a witness, even an expert witness, “may

temper their acceptance of his [or her] testimony with a healthy

skepticism born of their knowledge that all human beings are

fallible.” (People v. McDonald (1984) 37 Cal.3d 351, 372; accord,

People v. Jones, supra, 57 Cal.4th at p. 953.) For this reason,

“ ‘[a]bsent some special feature which effectively blindsides the

jury, expert opinion testimony is not subject to Kelly[].’ ” (People

v. Eubanks (2011) 53 Cal.4th 110, 140, quoting People v. Stoll

(1989) 49 Cal.3d 1136, 1157.) Of course, some expert testimony

may be “based, in whole or part, on a technique, process, or

theory which is new to science and, even more so, the law” (Stoll,

at p. 1156); where the novel technique “appears in both name

and description to provide some definitive truth which the

expert need only accurately recognize and relay to the jury,”

additional scrutiny under Kelly is warranted. (Ibid.; see People

v. Cowan (2010) 50 Cal.4th 401, 470.) But this case does not fit

that description.

Dr. Cheng began with an overview for the jury of how

various forces, including tides, currents, and wind, interact and

affect the waters of the bay. He then explained how, given the

time and location where Conner’s body was found, he worked

backward to estimate where Conner was most likely to have

started. Tidal currents in the area were weak and would likely

have canceled out, so Dr. Cheng treated wind-driven drift as the

principal force that would have moved Conner’s body to shore.

He accepted as a starting assumption the hypothesis that Laci

and Conner had been weighted down and then broken free and

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treated Conner as a floating body thereafter. Performing

calculations using an equation drawn from the United States

Army Corps of Engineers Coastal Engineering Handbook to

translate measured wind speeds into a corresponding rate of

water movement, Dr. Cheng worked backward to estimate the

most probable path Conner’s body would have followed.

Dr. Cheng’s modeling involved no novel technique. The

study of tides and currents and their effect on the motion of

bodies in water is hardly new. Nor is the scientific

understanding of how wind affects the movement of water —

and thus bodies in water — of recent origin. Indeed, as

Dr. Cheng explained to the jury, much of his modeling involved

applying established, published equations to the known

conditions in the hours and days before Conner’s and Laci’s

bodies were found. The application of settled principles to

estimate the motions of bodies in water did not require a Kelly

hearing.

While the absence of a novel technique alone disposes of

Peterson’s Kelly argument (see People v. Stoll, supra, 49 Cal.3d

at p. 1156), we also note that, as described by Dr. Cheng, the

technique was not one that carried a “misleading aura of

scientific infallibility” (id. at p. 1157) — the primary danger

Kelly is designed to guard against. Dr. Cheng apprised the jury

of the ways in which the model’s accuracy was dependent on a

host of initial assumptions, many of which carried with them a

considerable degree of uncertainty. For example, it was

unknown when Conner’s body had actually washed ashore,

which would have altered best estimates of his starting point,

and no starting point could be estimated at all for Laci, who was

found a day later at a point nearly one mile away from Conner.

Moreover, because divers found no evidence to confirm Conner

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or Laci had ever been at the starting location Dr. Cheng

suggested, the jury had ample basis to take his opinions with

more than a dash of salt.20 Because Dr. Cheng’s testimony did

not describe to the jury a mechanistic process that pointed

unerringly to firm conclusions, it presented no risk of

blindsiding the jury and precluding it from critically evaluating

his ultimate opinion. (See People v. Garlinger (2016) 247

Cal.App.4th 1185, 1196–1197 [no risk jury would accord aura of

infallibility to cell phone networks expert who “did not purport

to be able to determine the precise location” of a cell phone].)

Peterson relies heavily on People v. Leahy (1994) 8 Cal.4th

587, but Leahy bears no resemblance to the case here. There,

police officers testified to the results of a “ ‘horizontal gaze

nystagmus’ ” test purported to reliably indicate intoxication.

(Id. at p. 605.) We explained that the test was a “ ‘new’ ”

technique for purposes of Kelly. (Leahy, at p. 606.) Further,

with its “ ‘ “pretentiously scientific name,” ’ ” the test was one

that might “appear[] to provide to the jury a ‘definitive truth.’ ”

(Ibid.) As such, the test involved the precise risk underlying the

exception to the rule that expert testimony need not satisfy

Kelly — it was a novel technique that “appears in both name and

description to provide some definitive truth which the expert

need only accurately recognize and relay to the jury.” (People v.

Stoll, supra, 49 Cal.3d at p. 1156.) The same is not true of the

methodology underlying Dr. Cheng’s testimony.

20

Indeed, recognizing that Dr. Cheng’s testimony might

help the defense as much as it hurt, defense counsel said before

Dr. Cheng testified, “[I]n some ways, I want it to come in

because I believe his ultimate conclusion is that he can’t say

anything about Laci.”

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Peterson also criticizes the extent of Dr. Cheng’s expertise

as it relates to the motion of objects in fluids, as opposed to the

motion of fluids themselves. The criticism is not well taken. For

one, Dr. Cheng had a Ph.D. in aeronautical engineering and had

studied the movement of drifters, devices used to measure

currents at the surface and at depth. For another, such

criticisms go to the weight a jury might accord Dr. Cheng’s

testimony, but not its admissibility or whether Kelly foundation

was required. (See People v. Eubanks, supra, 53 Cal.4th at

p. 143.) Peterson did, in fact, raise his concern about

Dr. Cheng’s background during cross-examination, and the jury

could consider that concern.

In sum, Dr. Cheng, an expert hydrologist, could offer his

opinion as to the most probable movement of Conner’s body in

the San Francisco Bay without the court first conducting a Kelly

hearing. The court did not abuse its discretion in admitting his

testimony.

F. Issues Concerning the Stability of Peterson’s

Boat

1. Exclusion of Videotaped Defense Demonstration

During the defense’s presentation of evidence, the court

held an Evidence Code section 402 hearing to evaluate the

admissibility of a videotaped experiment the defense had

conducted from a boat on the San Francisco Bay. In the

experiment, an employee of defense counsel’s law firm tried to

push a 150- to 155-pound dummy out of the boat. The boat

partially sank before the employee abandoned ship.

The prosecution submitted a litany of objections. From the

videotape, it was not possible to determine the kind of boat used

because identifying features had been covered up; the boat’s

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seats were mounted on wood, thus raising the boat’s center of

gravity; the boat had a different motor than Peterson’s boat; the

person performing the experiment was wearing a weight belt

that impeded his movements; nothing established the prevailing

tides, currents, and waves, or how closely they approximated the

conditions on December 24, 2002; nothing established the

location of the experiment; the boat’s gas tank and batteries

were located in different positions than on Peterson’s boat; the

boat had plywood decking added, which could affect its stability;

the dummy got wet, which would have added weight; the boat

was already starting to take on water before the employee even

tried to dump the dummy; and the employee performed the

experiment while standing on the boat’s gunwales, which

suggested he was “intentionally trying to sink the boat.” After

reviewing the tape, the court ruled it inadmissible under

Evidence Code section 352. Peterson contends this was error.

“ ‘Under Evidence Code section 352, the trial court has

wide discretion to admit or reject experimental evidence. We

reverse decisions to admit or exclude such evidence only when

the trial court has clearly abused its discretion.’ ” (People v.

Jones (2011) 51 Cal.4th 346, 375–376.) Before experimental

evidence may be admitted, the proponent must establish that

the experiment is relevant, was “ ‘ “conducted under

substantially similar conditions as those of the actual

occurrence,” ’ ” and will not mislead or confuse the jury or take

undue time. (Jackson, supra, 1 Cal.5th at p. 342.)

The prosecution raised a host of ways in which the defense

did not carry its burden of establishing that its demonstration’s

conditions sufficiently resembled conditions on December 24,

2002. The court could and did rely on these points, including

Peterson’s failure to establish the similarity of the boat used, the

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weather, and the location. From our own review of the proffered

video, we cannot say the court abused its broad discretion to

determine the video’s admissibility. (See People v. Jones, supra,

51 Cal.4th at pp. 375–376.) The video shows the waters of the

bay were extremely choppy during the experiment. Even before

the defense employee tried to hoist the dummy, the boat was

taking on water because the employee was stepping on the

boat’s gunwale, on the same side as an elevated seat (Peterson’s

boat had no similar elevated seat) and the side toward which the

boat’s roughly 75-pound motor had been angled. This

concentration of weight allowed waves to break over the boat’s

gunwales. However stable the boat might have been if attempts

were made to counterbalance, no such attempts were made in

the defense’s demonstration. The boat also had plywood decking

added, which would have not only raised the center of gravity,

but also concealed whatever might have lain underneath.

Peterson emphasized to the trial court that it had already

admitted evidence of a prosecution experiment in which a

district attorney’s office employee, also late in her third

trimester of pregnancy and weighing the same as Laci, lay down

in Peterson’s boat to show how someone could fit without being

noticeable. Peterson strenuously argued that, by parity of

reasoning, his experiment should be admissible too. He makes

the same point on appeal. But the two situations are not

symmetric, and that asymmetry explains why a court could

exercise its discretion to admit one experiment but not the other.

As discussed, Peterson laid no foundation establishing the

extent to which the conditions during his videotaped experiment

mirrored those that would have obtained during the alleged

disposal of the body. In contrast, the prosecution’s photographs

showed precisely the feasibility of what they posited had

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occurred — that the body of a pregnant, 153-pound woman could

be curled to fit in the bottom of Peterson’s actual boat.

The two experiments are asymmetric in a second way as

well. A person trying to dispose of a body by dumping it out of

a boat into the bay would have had every incentive to

counterbalance against the body’s weight in order to avoid

capsizing the boat. The defense firm’s employee, in contrast,

had an incentive to undermine the experiment’s results, and

indeed the prosecution argued that the video showed he was

trying to do just that. To be sure, the prosecution’s employee

had an incentive to make herself fit, but that incentive does

nothing to detract from the persuasive force of the prosecution’s

experiment as evidence of the possible. No matter how much

the pregnant employee might have wanted to make the

demonstration work, she could not have unless it was, in fact,

possible for her to fit her body in that space. As the court noted,

“All she had to do was lay there. She didn’t have to demonstrate

throwing something — throwing something in the water.”

Consequently, while the defense demonstration was not

irrelevant, it was within the court’s discretion to conclude the

defense had not laid sufficient foundation to establish the

demonstration — conducted in a different boat, under different

conditions, by a defense employee — bore a sufficiently close

resemblance to how Peterson allegedly disposed of Laci’s body,

so as to avoid misleading the jury. That the trial court admitted

photographs of the prosecution’s demonstration does not alter

this conclusion.

The refusal to admit the video was likewise not erroneous

under federal law. Peterson argues that the exclusion of the

evidence violated his rights under the Fifth and Sixth

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Amendments to a fair trial and to submit evidence relevant to

the question of guilt. (See Pennsylvania v. Ritchie (1987) 480

U.S. 39, 56; Chambers v. Mississippi (1973) 410 U.S. 284, 294.)

Here, however, the court reasonably found the evidence to be

unreliable and misleading. The Constitution contains no right

to admit such evidence.

2. Conditions on Reprise of Defense Experiment

In the course of ruling the defense’s boat experiment

inadmissible, the court made clear it was not categorically

barring any such experiment, only the experiment as originally

conducted and submitted. Counsel complained that the ruling

gave the defense no way to oppose the prosecution’s case. While

cautioning that it was “not here to give you advice,” the court

offered two ways in which the defense might choose to modify

the experiment to increase its odds of admissibility: “Number

one, you take out the original boat instead of this boat. [Number

two, y]ou have someone that doesn’t work for you conduct the

experiment, you know. That would be two things that are out of

the way.” The court also suggested the defense try to establish

what the conditions were like on the day Peterson was alleged

to have dumped Laci’s body in the bay.

Shortly after denying admission of the defense’s boat

experiment, the court voluntarily revisited the issue and again

made clear the defense could redo the experiment in a way that

might make it admissible, if it so chose. The court offered the

defense access to Peterson’s boat to redo the experiment, adding

“I think you should have representatives of the [P]eople there to

observe what happens.” Later, the court reiterated, “I’m willing

to let you have the boat. I’m willing to let you put the 150-pound

person in it. I’m willing to let you have somebody, but I want

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the prosecution to be present and watch the way this thing went

down. What’s wrong with that?” The court also said it would be

helpful if the reenactment included footage showing where

Brooks Island was, relative to the demonstration, and was

conducted in the general area the prosecution’s expert,

Dr. Cheng, had suggested was most likely. If the defense

wanted to redo the experiment with some adjustments, the court

offered to revisit its ruling. Ultimately, Peterson elected not to

redo the experiment.

Peterson now contends that by offering to revisit its

ruling, but conditioning access to the boat on the prosecution

being able to observe any reenactment, the court committed

presumptively prejudicial error compelling automatic reversal.

Peterson has not preserved any claim of error.

During the Evidence Code section 402 hearing on

admissibility of the defense’s video and its aftermath, Peterson

did not object to the trial court’s suggested condition, even as the

court invited objection by asking, “What’s wrong with that?”

Nor did Peterson move for the court to grant him access to the

boat and to lift any condition that a member of the prosecution

view experiments with that boat, or in any other way object to

the court’s conditional offer of access to Peterson’s boat. Instead,

counsel thanked the court for its openness to revisiting its

decision and said he would check the weather for suitable

conditions and confer with his client.

At the close of the Evidence Code section 402 hearing,

then, here is where matters stood. The defense had presented a

video of a demonstration on the bay, and the court had —

permissibly, as we have just discussed — exercised its discretion

to exclude that video. The court had also, sua sponte, made clear

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that its ruling did not foreclose a future attempt to videotape a

further demonstration and resubmit a video for consideration.

And finally, the court had suggested different ways the defense

could modify the original experiment, if it so chose, including

(1) using a different test subject, unaffiliated with the defense,

to perform the experiment or (2) using the Peterson boat, with a

prosecution observer. Peterson did not object to the latter

condition; he instead let the matter drop.

The People argue that because Peterson elected not to

conduct an experiment with the prosecution present, he has

forfeited any claim on appeal. This goes too far. To preserve a

claim that the court has unconstitutionally placed a condition

on the defendant’s introduction of evidence, a defendant need

not always comply with the condition. (See, e.g., United States

v. Nobles (1975) 422 U.S. 225 [addressing the merits after the

defendant declined to comply with an allegedly unconstitutional

condition and elected not to have a witness testify].) But if the

defendant objects to the condition, he does need to make his

objection known (see, e.g., People v. Varghese (2008) 162

Cal.App.4th 1084, 1090–1091), unless doing so would be futile

(People v. Perez (2020) 9 Cal.5th 1, 7–8). Here, nothing in the

record suggests it would have been futile to raise the issue with

the trial court. It appears the trial court was merely throwing

out ideas as to how the defense could redo the experiment in a

way that would address the deficiencies of its first effort, not

giving its final word on the subject.

In this and other respects, this case differs from Prince v.

Superior Court (1992) 8 Cal.App.4th 1176, 1179–1181, which

held that a trial court could not condition the ability of the

defense to test a critical DNA sample on disclosure of any results

to the People. Here, we do not know whether the trial court

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actually and finally conditioned the defense team’s ability to test

the stability of the Peterson boat on the presence of a

prosecution observer, because Peterson never raised any

concerns about the trial court’s offer to revisit its exclusion

ruling under those circumstances. Had the court said nothing

at all after excluding the original, flawed demonstration,

Peterson would have no argument. That the court volunteered

one way in which Peterson could rectify the problems with the

original demonstration did not inject constitutional error into

the proceedings, let alone presumptively prejudicial error

compelling automatic reversal.

3. Prosecutorial Misconduct in Closing Argument

During closing argument, the prosecution addressed the

stability of Peterson’s boat. According to the prosecutor,

although the defense had insinuated a boat like his was “ready

to tip over at the drop of a hat” and would have capsized if

Peterson had tried to push Laci’s body overboard, “there’s no

evidence [the boat] would have done that.” He recounted the

testimony of prosecution witnesses indicating the boat was

stable enough to pull heavy fish on or push heavy weights off

and concluded, “There’s no evidence to contradict that

whatsoever.” Peterson argues these comments were reversible

misconduct because they improperly took advantage of the

exclusion of the defense’s evidence about the boat’s instability.

We disagree; this was not misconduct.

“Prosecutorial misconduct requires reversal when it ‘so

infect[s] a trial with unfairness [as to] create a denial of due

process. [Citations.] Conduct by a prosecutor that does not

reach that level nevertheless constitutes misconduct under state

law, but only if it involves the use of deceptive or reprehensible

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methods to persuade the court or jury.’ ” (People v. Armstrong,

supra, 6 Cal.5th at p. 795.)

Preliminarily, Peterson has forfeited his claim that the

prosecutor engaged in prejudicial misconduct. To preserve a

claim for review, a defendant must object and ask that the jury

be admonished concerning the misconduct. (People v. Daveggio

and Michaud (2018) 4 Cal.5th 790, 853; People v. Bryant, Smith

and Wheeler (2014) 60 Cal.4th 335, 426–427; People v. Watkins

(2012) 55 Cal.4th 999, 1031.) Peterson concedes he did not

object, but contends objection was excused because prosecutors

are held in such high regard that no admonishment from a court

could cure any harm. If Peterson were correct, then no criminal

defendant would ever need object to perceived prosecutorial

misconduct. The case law is, of course, to the contrary. (See

People v. Panah (2005) 35 Cal.4th 395, 462 [“A defendant

claiming that one of these exceptions [to the objection

requirement] applies must find support for his or her claim in

the record. [Citation.] The ritual incantation that an exception

applies is not enough.”].) Alternatively, Peterson argues that

counsel was ineffective for failing to object. But counsel’s

performance was not deficient; any such objection would have

been meritless and properly overruled.

As the record stood at the close of the guilt phase, there

was, in fact, no evidence affirmatively supporting the argument

that Peterson’s boat was too unstable for Peterson to have

thrown Laci off it. Peterson cross-examined the prosecution’s

witnesses in an attempt to cast doubt as to whether their

testimony adequately established the boat’s stability. But

Peterson introduced no evidence of instability to contradict that

testimony. The prosecution’s observations about this omission

were thus fair comment on the state of the evidence.

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Peterson does not contend otherwise, but instead urges

that the only reason the record contains no such evidence is that

the prosecution moved, successfully, to exclude the

aforementioned video of the defense’s demonstration in which a

surrogate boat capsized. In Peterson’s view, it was misconduct

for the prosecution to obtain the exclusion of evidence and then

comment on the resulting evidentiary vacuum.

That is not the law, as we explained in People v. Lawley

(2002) 27 Cal.4th 102 (Lawley). In Lawley, the defendant sought

to introduce evidence of third party culpability, but the court

excluded it at the prosecution’s urging — a ruling we upheld as

correct. (Id. at pp. 151–155.) The prosecutor then argued in

closing that no one but the defendant had a motive to kill the

victim. The defendant urged this as misconduct, but we

explained that, in light of the court’s correct evidentiary rulings,

the prosecution’s argument was fair comment on the record as

it stood. (Id. at p. 156.) Lawley makes clear that it is not

misconduct for the prosecutor to argue in closing that there was

no evidence supporting a particular proposition after the trial

court has properly excluded evidence the defense had sought to

introduce on that point.

Peterson relies on other cases, but they do not establish

that the prosecution is barred from ever remarking on an

evidentiary gap after successfully moving to exclude evidence

that would have filled that gap. The only two California cases

he cites, People v. Daggett (1990) 225 Cal.App.3d 751 and People

v. Varona (1983) 143 Cal.App.3d 566, were likewise invoked by

the defendant in Lawley; we distinguished them as “inapposite”

because “each involved erroneous evidentiary rulings on which

the prosecutor improperly capitalized during his closing

argument.” (Lawley, supra, 27 Cal.4th at p. 156, italics added.)

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Here, by contrast, there was no error in the exclusion of the

evidence.21

Peterson’s cases from other jurisdictions are likewise

distinguishable because each involved erroneously excluded

evidence or a prosecutor deceiving the jury into making

inferences the prosecutor knew to be untrue. (Cf. Paxton v.

Ward (10th Cir. 1999) 199 F.3d 1197 [prosecution misled the

jury as to the reason charges against the defendant for a prior

shooting had been dropped]; U.S. v. Ebens (6th Cir. 1986) 800

F.2d 1422 [reversal required where the prosecution suggested to

the jury inferences it knew to be untrue]; U.S. v. Toney (6th Cir.

1979) 599 F.2d 787 [erroneous exclusion of evidence

corroborating the defendant’s story prejudicial because the

prosecution stressed the absence of corroborating evidence];

State v. Bass (1996) 121 N.C.App. 306 [465 S.E.2d 334]

[prosecution argued inference to the jury that it knew to be

untrue].) These cases involved “ ‘deceptive or reprehensible

methods to persuade the court or jury.’ ” (People v. Armstrong,

supra, 6 Cal.5th at p. 795.) Here, instead, the prosecutor

commented fairly on the record. There was no misconduct.

21

Our recent decision in People v. Armstrong, supra, 6

Cal.5th 735, is similarly distinguishable. There, we found

misconduct after a prosecutor persuaded the trial court to

exclude defense evidence of what the victim said before she was

attacked — evidence that should have been admitted — and

then attributed to the victim a different statement nowhere

supported in the record. (Id. at pp. 785–787, 796–797.) The

prosecutor here, in contrast, commented only on the admissible

evidence and did so accurately.

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4. Juror Examination of the Physical Evidence During

Deliberations

Peterson’s boat was admitted into evidence. During trial,

the jury was given the opportunity to inspect it. During

deliberations, the jurors asked to look at the boat again. The

court agreed and had them do so with the prosecution and

defense present. Some jurors asked to sit in the boat. The court

acquiesced, reasoning that they should be permitted to test for

themselves the evidence the prosecution had submitted

concerning how a person (or body) could fit in the bottom of the

boat. While in the boat, at least two jurors stood and, by shifting

their weight back and forth, rocked the boat. The court

cautioned the jurors that they should keep in mind the boat was

secured on a trailer, not in the water. Peterson argued that the

jurors’ attempts to rock the boat constituted an impermissible

experiment and sought an opportunity

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