The opinion
FORT, J.,
dissenting.
Defendant was convicted by a jury on four counts of robbery in the first degree. The offenses were committed in the early morning hours by at least three armed men, wearing stocking masks. The trial commenced on April 4, 1973. On that day, just prior to its commencement, the state informed the defendant that John Costello, an alleged accomplice of defendant in the commission of the crime, would testify for the state. Until that time the state had consistently informed the defendant that Costello was in a mental institution, was incompetent and would be unable to testify.
The court held a hearing in the absence of the jury during the trial to consider whether Costello, who on that day was brought to court from the state mental hospital, was competent. A major portion of the testimony related to his capacity to remember. Two psychiatrists were called. One said he was competent to testify, and the other said» he was not. The court ruled he was competent to testify. He was then called as a witness by the state, having first been granted immunity from prosecution.
During cross-examination of Mr. Costello, the following transpired:
“Q. [by defense counsel] Do you have a fairly
good memory, Mr. Costello ?
“A. Yes.
* # # #
*24 “Q. Mr. Costello, you’ve indicated that you have a good memory. Can you remember who the President of the United States is?
“A. No.
“THE COURT: Just a minute. We went through that this afternoon. Go ahead, for the record.
“MR. YOUNGMAN [deputy district attorney] : I object to that as being irrelevant.
“THE COURT: The objection is sustained, and I don’t want you to go through any questions we discussed at this hearing this morning when I had to rule on the ability of this witness, whether he was competent or not to testify.
“Q. (By Mr. Susak) Mr. Costello, do you know a gentleman by the name of Max Sagner?
“A. Yes.
“Q. Why don’t you describe Mr. Sagner for me, please ?
“MR. YOUNGMAN: I object to that as well, unless counsel can tie that up as to its relevance.
“THE COURT: Are you representing it’s relevant to this case?
“MR. SUSAK: Yes, Your Honor.
“THE COURT: All right. I’m going to permit you to ask him, if it’s relevant to this case, but you’re not going to go into questions to test him upon his ability to testify because I’ve already ruled on that. It’s up to the jury to weigh his testimony.
# * # *
“THE COURT: Now before we proceed any further, Mr. Susak, I want to clarify my ruling a while ago when I said I’m not going to let you go into matters we covered such as does he know who the President is. If you want to ask any questions relevant to the incident or the alleged robberies, that might test his memory that night, that’s fine, *25 but on the matters that aren’t relevant as to what happened that night, as I indicated, I’m directing you not to — * * * — ask him.”
3 Wharton, Criminal Evidence 266-67, § 871 (Anderson 1955) states:
“Cross-examination to impeach, diminish, or impair the credit of the witness is not confined to matters brought out on the direct examination. The witness may be cross-examined as to collateral matters not embraced in the direct examination to test credibility and veracity.
“Any question is allowed which reasonably tends to explain, contradict, or discredit any testimony given by the witness in chief, or which tends to test his accuracy, memory, veracity, character, or credibility. Great latitude is allowed in cross-examination upon matters bearing upon the witness’ credibility. Any cross-examination which permits an insight, into the credibility of the witness is permissible. Inasmuch as the jurors are the sole judges of the credibility of the witness, any matter that will properly assist the jurors in forming a correct judgment from all the facts ought to be shown in evidence. * * *"
McCormick, Evidence 93, § 45 (hornbook series 1972) points out the distinctions between attacks on competency and credibility as follows:
“As to the mental qualities of intelligence and memory, a distinction must be made between attacks on competency and attacks on credibility, the subject of this section. Sanity in any general sense is not the test of competency, and a so-called insane person may testify if he is able to report correctly the matters to which he testifies and if he understands the duty to speak the truth. Manifestly, however, the fact of mental ‘abnormality’ either at the time of observing the facts or at the time of testifying will be provable, on cross or by extrinsic evidence, as bearing on credibility. * * *”
*26 In State v. Miskell, 161 NW2d 732, 735 (Iowa 1968), the court said:
“58 Am. Jur., Witnesses, section 699, pages 378, 379, states: ‘A person without memory is valueless, if not incompetent, as a witness. Hence, any evidence going to show that the mind and memory of the witness are impaired by disease or otherwise, and are in a feeble condition, is competent to discredit his testimony. This is permissible even though the witness may not be mentally incompetent to testify.’ For like statements see 98 C.J.S. Witnesses §§ 461 (f), 486, and 3 Wigmore, 3rd Ed., section 931.
“Testimony is admissible to impeach a witness by showing his mind and memory have become inpaired [sic] and in an abnormal condition. State v. Alberts, 199 Iowa 815, 818, 819 , 202 N.W. 519, 521 ; Alleman v. Stepp, 52 Iowa 626, 629 , 3 N.W. 636, 637 . Such evidence is admissible on cross-examination of the witness. [Citations omitted.]”
In Walley v. State, 240 Miss 136, 126 So2d 534, 535 (1961), the court said:
“* * * We think the case must be reversed for the exclusion of certain evidence proffered by defendant’s counsel in his cross-examination of Ellis, the State’s chief witness. The defense has a right on cross-examination to interrogate the State’s witnesses concerning their mental capacity, perception, memory and trustworthiness. These were especially important issues as to Ellis. On cross-examination of him, counsel asked Ellis whether he was confined in a mental hospital in San Antonio, Texas two years ago. The district attorney’s objection to this question was sustained. It should have been overruled. Whether Ellis has a history of previous mental disorders was a relevant fact for the jury to consider in determining his veracity.”
*27 In Ellarson v. Ellarson, 198 App Div 103 , 190 NYS 6, 9 (1921), the court said:
“Having passed the examination by the court and been sworn, the mental capacity of the witness may be tested and considered as bearing upon her credibility and her degree of intelligence. In Wigmore on Evidence, vol. 2, § 932, it is said:
“ ‘The existence of a derangement of the sort termed insanity is admissible to discredit, provided that it affected the witness at the time of the affair testified to, or while on the stand or in the meantime so as to cripple his powers of recollection.’ ”
See also: Sturdevant v. State, 49 Wis 2d 142 , 181 NW2d 523, 526 , 44 ALR 3d 1196 (1971); 98 CJS 326, Witnesses, § 461.
In its brief the state acknowledges “[i]t may, indeed, be questioned whether the court’s ruling on this matter was entirely correct. * * *[I]t is at least arguable that some general questions concerning a witness’ memory and mental condition are permissible on cross-examination, for their bearing on the witness’ credibility.” But, it contends, “the rulings complained of in this assignment of error [do not] warrant reversal.” I disagree.
The psychiatrist who testified he considered Mr. Costello competent to testify said:
“I think that he’s competent to relate the events pertaining to this burglary. He has a lot of deficits, as has been pointed out in front of us, as to his intellectual capabilities, but he can relate in a logical sequence the facts that happened to him during his lifetime, and part of his memory deficit, I think, is related to the treatment that he has had at the hospital. He was very, very ill when he came in and he didn’t respond to medication, so that we gave *28 him a few electroshock treatments, and one of the side effects that usually is very self-limiting following this, and I think that his memory is sufficiently returned and I think that he can remember well enough events that have happened in his life, that I would consider him to be competent.”
He also testified:
“He gets medication every night. He’s getting some major tranquilizers, Thorazine and Stelazine, and as he told you, he takes it at nighttime and this is hopefully to prevent these hallucinations that he has had frequently in the past. He is still sick, but I don’t think this is the main concern or factor in whether he can testify or is competent. I think he’s still mentally ill.
“THE COURT: Has he ever told you about any threats on his life in your interviews ?
“THE WITNESS: I think most of his hallucinations are persecutory. It’s the voices of his father and his brother, who I think are both dead, that keep telling him. to kill himself. ‘It’s your turn, we’re going to get you.’ And this is the thing I think that makes him so frightened and he has visions in his cell, or he did formerly, of somebody there that’s obviously got a weapon and trying to kill him. These are the things that have been causing him to be suicidal. I think he’s trying to escape these things.”
The other psychiatrist did not think Mr. Costello was mentally competent to be a witness at all.
Clearly then, his credibility as a witness was a significant issue both with respect to his capacity to remember and the degree of his current derangement. The court’s second ruling, supra, made on its own motion limiting the cross-examination “to the incident of the alleged robberies, that might test his memory that night, that’s fine, but on the matters that aren’t *29 relevant as to what happened that night, as I indicated, I’m directing you not to * * * ask him” foreclosed the defendant from relevant cross-examination to test Mr. Costello’s credibility. As such, it was clearly prejudicial. I would reverse.
I therefore do not agree with the conclusion that defendant here is barred because he did not make an offer of proof concerning the nature and extent of Costello’s current derangement. The nature and extent of that testimony was clearly known to the court from the hearing just previously held by it in the absence of the jury concerning Costello’s competency to testify as a witness. It is obvious from the record set forth above that such an offer would have served no purpose.
Accordingly, I respectfully dissent.