The opinion
Filed 7/30/25 P. v. Lamar CA4/1
NOT TO BE PUBLISHED IN OFFICIAL REPORTS
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COURT OF APPEAL, FOURTH APPELLATE DISTRICT
DIVISION ONE
STATE OF CALIFORNIA
THE PEOPLE, D086177
Plaintiff and Respondent,
v. (Super. Ct. No. FWV22003765)
CHRISTOPHER JAY LAMAR,
Defendant and Appellant.
APPEAL from a judgment of the Superior Court of San Bernardino
County, Michael Knish, Judge. Affirmed.
Sheila O’Connor, under appointment by the Court of Appeal, for
Defendant and Appellant.
Rob Bonta, Attorney General, Lance E. Winters, Chief Assistant
Attorney General, Charles C. Ragland, Assistant Attorney General, Eric A.
Swenson, and Elana Miller, Deputy Attorneys General, for Plaintiff and
Respondent.
A jury convicted Christopher Jay Lamar of seven counts related to the
robbery of a jewelry store: two counts of robbery (Pen. Code, § 2111), three
counts of assault with a semiautomatic firearm (§ 245, subd. (b)), and two
1 Further undesignated statutory references are to the Penal Code.
counts of possession of a firearm by a felon (§ 29800, subd. (a)(1)). The jury
also found true allegations that Lamar personally used a firearm during the
commission of the robberies and assaults (§§ 12022.5, subds. (a), (d),
12022.53, subd. (b), 1192.7, subd. (c), 667.5, subd. (c)) and was personally
armed while unlawfully possessing a firearm (§ 12022, subd. (a)(1)). The
court sentenced Lamar to an aggregate prison term of 50 years to life, plus
seven years four months. Lamar timely appealed.
Lamar asserts the court prejudicially erred by allowing the
investigating detective to testify as an expert about cell phone call detail
records. The People contend the detective had sufficient qualifications to
testify as an expert on the subject, and, alternatively, any error in the
admission of her testimony was harmless.
We conclude the trial court did not prejudicially err in admitting the
testimony. We, therefore, affirm the judgment.
FACTUAL AND PROCEDURAL BACKGROUND
I. Robbery
On October 15, 2022, two men entered a jewelry store wearing black
clothing and masks and said, “This is an assault.” One of the men wore a
“uniform” jacket and carried a gun. The store owner told the men law
enforcement was coming and activated an alarm. The man wearing the
uniform jacket ran to her and said, “Hell no.” He put his gun to her head,
and then he hit her twice on the head with the weapon. The man took gold,
jewelry, and two cell phones from the owner’s desk and asked, “Where is the
cash, Bitch?” The other man broke display cases. The suspects also pointed
their guns at a man shopping in the store and ordered him to the ground.
The suspects stole over $20,000 worth of merchandise.
Around the time of the robbery, a witness driving in the shopping
center parking lot saw a car speed up to her, almost hitting her. The witness
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then saw two men in masks run out of the jewelry store and get into the car.
She took a picture of the car’s license plate and provided the information to
investigating officers.
II. Recovery of the Suspect Vehicle and the Cell Phones
On the evening of the robbery, a deputy sheriff located the suspect
vehicle parked near some train tracks. The vehicle was a silver Toyota
Camry registered to Angel Olvera.
A couple of days later, the store owner’s daughter found the owner’s
stolen cell phones near the same train tracks, less than 1,400 feet from where
police located the Camry.
III. Lamar’s Arrest
On October 19, 2022, investigating officers learned Lamar was
suspected in the robbery, and he was at a mall. They located Lamar inside
the mall, walking with David Goffney and another individual. The officers
approached Lamar when he returned to his vehicle. Lamar fled on foot.
After a short chase, the officers apprehended Lamar in the mall parking lot.
Lamar admitted to having a loaded gun in his backpack. In the backpack,
officers found a black and tan, nonserialized gun.
IV. Angel Olvera’s Statements and Testimony
After locating and towing Olvera’s Camry, the officers notified him he
could pick up his vehicle at the sheriff’s station. When Olvera appeared at
the station, a detective questioned him about the jewelry store robbery.
Olvera told the detective he let Lamar take his Camry after Lamar
offered to buy it. The next day, the day of the robbery, Lamar and Goffney
picked Olvera up in the Camry; Goffney was driving. When Olvera got in the
back of the car, Lamar took Olvera’s cell phone, turned the phone off, and
told Olvera they had to go do something. Eventually, Lamar told Olvera they
were going to rob the jewelry store.
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Before entering the store, Lamar put on a security jacket, and Olvera
put on a sweatshirt, an Amazon delivery shirt, black pants, gloves, and a ski
mask that Lamar gave him. Lamar also gave him a black gun. Lamar had a
“brown” gun. Goffney then dropped Lamar and Olvera off, and they entered
the jewelry store.
Inside the store, Olvera saw Lamar hit the store owner. Olvera broke a
display case, took a pearl necklace, and left the store. He later gave the
necklace to Lamar and Goffney.
After the robbery, the men parked the Camry and drove away in a
Lexus.
Olvera was charged for his participation in the robbery, and he entered
into a plea agreement. Pursuant to the agreement, he pleaded guilty to one
count of second degree robbery and one count of assault with a semiautomatic
firearm, with firearm enhancements and the admission of one strike prior.
He agreed to testify truthfully against Lamar.2
Olvera’s testimony at Lamar’s trial was largely consistent with his
statements to the investigating officers, but with some additional details.
Specifically, at trial, Olvera testified Lamar used a black and tan gun during
the robbery, and Lamar threw the store owner’s cell phones out of the car
near the train tracks. Olvera also admitted he lied to the detective about
some details to mitigate his involvement in the crime. For example, he told
the detective Lamar pointed a gun at him when they drove to the jewelry
store even though that never happened.
V. Other Evidence
2 Before Lamar’s trial, Goffney pleaded guilty to one count of robbery in
violation of section 211 for his participation in the robbery.
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Officers discovered photos of jewelry on Goffney’s cell phone, which
were taken shortly after the robbery. The store owner identified the jewelry
in the photos as items stolen from her store during the robbery.
In addition, surveillance video from the shopping center where the
robbery took place showed a silver or tan Camry apparently casing the area
on the morning of the robbery. The video also showed two suspects exit the
Camry at the time of the robbery and then later run back to the vehicle.
Surveillance video from inside the store showed one suspect wearing an
Amazon vest and the other suspect holding a black and tan gun.
A fingerprint examiner matched Lamar’s fingerprint to a print found
on the rear driver’s side door of Olvera’s Camry. A forensic biologist matched
Lamar’s and Goffney’s DNA to items found inside the Camry.
VI. Call Detail Records
A. Detective’s Testimony
During trial, the investigating detective testified the term “Call Detail
Records” refers to “a log of phone calls and text messages on a person’s cell
phone account.” She explained call detail records reflected the date and time
cell phone activity transpired, the duration of the activity, whether a call was
incoming or outgoing, and the number called or texted. When asked to
explain for the jury what a cell service tower was, the detective testified,
“We’re able to make phone calls because of the service towers around a
particular area.” She explained the call detail records allowed her to
determine what tower was used for a particular transaction, and thus,
estimate a rough location of the subject cell phone at the time of a call or text.
The detective then identified for the jury the call detail records
associated with Lamar’s cell phone. Based on the call records, Lamar’s cell
phone had call activity that connected through the tower “a couple hundred
feet from . . .” the jewelry store the day before the robbery. About 40 minutes
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after the first call, Lamar’s cell phone had call activity that connected
through a tower near the area where law enforcement located Olvera’s
Camry and the store owner’s cell phones. Throughout that day, there were
multiple calls between Lamar’s cell phone and Olvera’s cell phone. The
detective explained the significance of the call history on the day before the
robbery by testifying it is common for people to “research” or “case” target
areas before committing a crime.
According to the detective’s testimony, the call records further showed
that, on the day of the robbery, a call was placed between Lamar’s cell phone
and Olvera’s cell phone at 12:08 p.m. Lamar’s cell phone reflected another
call at 12:11 p.m., after which the phone had no activity until 3:14 p.m., when
Lamar’s cell phone called Goffney’s cell phone. The robbery occurred around
2:38 p.m.
The detective similarly testified with respect to the call detail records
associated with Olvera’s cell phone. Olvera’s cell phone showed no activity
between 2:01 p.m. and 2:47 p.m. on the day of the robbery. At 3:15 p.m. and
3:40 p.m., there were two calls placed between Olvera’s cell phone and
Goffney’s cell phone.
During cross-examination, the detective testified she received informal
training on call detail records and how to read them, and she had a “general
understanding of how cell towers work.” Lamar’s trial counsel moved to
strike all of the detective’s testimony about cell towers as being outside of her
personal knowledge; the trial court reserved ruling. The detective then
admitted that, when placing a call, a cell phone does not necessarily connect
through the nearest tower. Hypothetically, a cell phone could connect
through a tower “a couple of miles” away. Lamar’s cell phone could have
been 15 miles or more away from the tower near the jewelry store when the
tower registered the call activity on the day before the robbery. The detective
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qualified her testimony by explaining she was “not an expert” with respect to
determining the distance between a cell phone and a tower, which prompted
defense counsel to again move to strike her testimony. The trial court again
deferred ruling.
B. Evidence Code Section 402 Hearing and Ruling
After the close of evidence, the trial court conducted a hearing outside
the presence of the jury on the motion to strike the detective’s testimony
under Evidence Code section 402. Lamar’s defense counsel argued the
detective lacked sufficient scientific understanding of the data in the call
detail records to render an opinion regarding the location of a cell phone in
relation to a tower, and that her testimony was irrelevant.
The detective testified at the hearing that she had no engineering
training and never worked for a telecommunications company. She never
had a job involving work on cell towers, never attended trainings on how cell
towers work, and never had anybody explain to her the process of how a cell
signal connects to a tower.
The detective testified, however, she had conducted approximately 100
investigations involving call detail records. Before she became experienced
with call detail records, several senior officers explained how to read the data
contained in the records. Despite her knowledge of call detail records, she
was “unclear on the precise location somebody is when a cell phone is
connected to a tower.” Although she knew a cell phone connects to the
nearest available tower, she was unable to determine whether the cell phone
was “five feet, 15 feet, 25 feet” from the tower when the activity was recorded.
She believed other people might be able to determine the distance with more
scientific accuracy.
The trial court ultimately denied the motion to strike the detective’s
testimony. The court concluded the detective was “not a master expert” on
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cell towers, but she met the “minimum standards” to testify as an expert on
the subject. The court explained the detective’s testimony was admissible
“subject to the weight being decided by the jury.”
DISCUSSION
Lamar raises a single issue on appeal. He contends the trial court
prejudicially erred by allowing the investigating detective to testify as an
expert about call detail records related to the suspects’ cell phones. Lamar
contends the admission of the testimony denied him his federal constitutional
right to due process and violated state evidentiary rules.3 The People assert
the detective had sufficient qualifications with respect to the call detail
records to qualify as an expert. Alternatively, the People contend, if the court
erred by allowing the expert testimony, the error was harmless. We find the
trial court did not err by admitting the testimony, and regardless, any
potential error was harmless under any standard.
“ ‘California law permits a person with “special knowledge, skill,
experience, training, or education” in a particular field to qualify as
an expert witness (Evid. Code, § 720) and to give testimony in the form of an
opinion (id., § 801, [subd. (b)]). Under Evidence Code section 801, expert
opinion testimony is admissible only if the subject matter of the testimony is
3 Within his due process argument, Lamar also asserts the trial court
violated his Sixth Amendment right to have a jury determine all facts related
to his guilt. We do not expressly address this undeveloped contention.
(People v. Carroll (2014) 222 Cal.App.4th 1406, 1412, fn. 5 [court need not
consider constitutional argument void of analysis or authority].)
Nevertheless, for the same reasons discussed post, any Sixth Amendment
violation here was harmless. (People v. French (2008) 43 Cal.4th 36, 52
[“ ‘Failure to submit a sentencing factor to the jury, like failure to submit an
element [of the crime] to the jury, is not structural error[,]’ ” and thus, is
subject to harmless error review]; but see People v. Ernst (1994) 8 Cal.4th
441, 449 [total denial of right to jury trial on charged offense is a structural
defect].)
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“sufficiently beyond common experience that the opinion of an expert would
assist the trier of fact.” ’ ” (People v. Vang (2011) 52 Cal.4th 1038, 1044
(Vang).) “[E]videntiary objections based on lack of foundation,
qualification of experts, and conclusory and speculative testimony are
traditionally left to the sound discretion of the trial court.” (Alexander v.
Scripps Memorial Hospital La Jolla (2018) 23 Cal.App.5th 206, 226.) We will
not disturb the trial court’s exercise of that discretion in determining an
expert witness’s qualification “absent a showing of manifest abuse” such as
when “ ‘ “ ‘the evidence shows that a witness clearly lacks qualification as an
expert.’ ” ’ ” (People v. Jones (2012) 54 Cal.4th 1, 57 (Jones).)
The erroneous introduction of evidence against a defendant may violate
due process where the evidence “is so extremely unfair that its admission
violates ‘fundamental conceptions of justice.’ ” (Dowling v. United States
(1990) 493 U.S. 342, 352.) “For the erroneous admission of evidence to
amount to a denial of due process, the evidence must have been ‘ “sufficiently
material to provide the basis for conviction or to remove a reasonable doubt
that would have existed on the record without it.” ’ ” (People v. Dryden (2021)
60 Cal.App.5th 1007, 1025–1026.)
Under Chapman v. California (1967) 386 U.S. 18 (Chapman), a federal
constitutional error is harmless when it appears “beyond a reasonable doubt
that the error complained of did not contribute to the verdict obtained.”
(Id. at p. 24.) State law evidentiary errors are analyzed for harmless error
under the standard set forth in People v. Watson (1956) 46 Cal.2d 818, 836
(Watson). (People v. Hin (2025) 17 Cal.5th 401, 482.) “This requires us to
examine whether it was ‘reasonably probable that a result more favorable to
the appealing party would have been reached in the absence of the error.’ ”
(People v. Johnson (2022) 12 Cal.5th 544, 611.)
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Here, following the Evidence Code section 402 hearing, the trial court
did not abuse its broad discretion or deny Lamar due process by admitting
the detective’s testimony after carefully considering her qualifications,
including her training and experience. The court concluded she had the
minimum qualifications to testify about the call detail records. The court
properly left the weight of her testimony to the jury. (Jones, supra, 54
Cal.4th at p. 59 [“Once an expert witness establishes knowledge of a subject
sufficient to permit his or her opinion to be considered by a jury, the question
of the degree of the witness’s knowledge goes to the weight of the evidence
and not its admissibility.”].) Nevertheless, any potential error was harmless
under either standard.
Lamar contends the admission of the detective’s testimony about the
call detail records was prejudicial because the cell phone evidence was the
only thing corroborating Olvera’s statements implicating Lamar. We
disagree. Setting aside the detective’s testimony, substantial evidence
corroborated Olvera’s account that he, Lamar, and Goffney committed the
robbery using Olvera’s Camry. A vehicle matching Olvera’s Camry was seen
in surveillance video near the jewelry store before the crime. Video also
showed the suspects wearing the clothing Olvera described. The witness in
the parking lot saw the suspects run away from the jewelry store and get into
Olvera’s Camry, and the surveillance video confirmed her account. Forensic
evidence placed both Lamar and Goffney inside the Camry. Lastly, Lamar’s
associate, Goffney, had photos of the stolen jewelry on his cell phone.
Lamar further asserts that, absent the cell phone testimony to
corroborate Olvera’s identification of Lamar as one of the robbers, the
remaining evidence implicated Goffney as the person who robbed the store
with Olvera. But ample evidence apart from the cell phone data supports the
conclusion Lamar was in the store. The store owner described the suspect
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with the uniform jacket as “tall” and “skinny.” Lamar was described at trial
as taller and skinnier than Goffney. In addition, surveillance video
established the suspect who entered the store with Olvera used a gun with a
distinct black and tan color pattern. Lamar was arrested while in possession
of a matching gun. Lamar did not present any evidence to dispute Olvera’s
claim that Goffney was wearing a white T-shirt on the day of the robbery,
and surveillance video showed the driver of the Camry wearing “[a] very light
color or white” shirt. On the other hand, surveillance video showed the
passenger of the Camry had a yellow shield on the chest area of his clothing,
which was consistent with the suspect who wore the security jacket inside the
jewelry store.
On this record, we agree with the People that it is “beyond a reasonable
doubt that the error complained of did not contribute to the verdict obtained.”
(Chapman, supra, 386 U.S. at p. 24.) It is also not reasonably probable that
absent the cell tower testimony the jury would have acquitted Lamar. (See
Watson, supra, 46 Cal.2d at p. 836.)
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DISPOSITION
The judgment is affirmed.
McCONNELL, P. J.
WE CONCUR:
IRION, J.
CASTILLO, J.
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