Defendant pleaded guilty to first degree murder, and a jury fixed the penalty at death. On appeal the judgment was reversed insofar as it related to the penalty but affirmed in all other respects. (People v. Hines, 61 Cal.2d 164 [37 Cal.Rptr. 622, 390 P.2d 398].) At the second penalty trial a jury again imposed the death penalty. Motions for a new trial and for reduction of penalty were denied, and defendant’s second automatic appeal is now before us (Pen. Code, § 1239, subd. (b)).
About midnight on July 1, 1962, the body of Billy Cooper was found behind the counter of Mary’s liquor store, where he had worked, on Lincoln Boulevard in Venice. An autopsy revealed that death was caused by multiple gunshot wounds, the major ones being in the head and heart. The bullets removed from the body were .32 caliber.
The police found one .32 automatic cartridge case on the customer's side of the counter and four such cases on the other side of the counter. A .22 revolver was by the body. No .22 caliber slugs were found in the store but in the store ceiling the police saw what appeared to be bullet holes of a .22 caliber projectile.
The police had but few clues, had no idea that defendant was involved in the killing, and so, of course, were not looking for him. Although a description of the killer was secured and published, this description only vaguely resembled defendant.
About 2:15 p.m. on July 11, 1962, defendant walked into the Venice police substation. The desk officer took him into the *351office of Officer Hestand and said, ‘ ‘ This man just came to the desk next door and he put the gun and a sack of ammunition on the desk, and he said, ‘Are you looking for the man that killed the clerk in the liquor store on Lincoln Boulevard a couple of weeks ago?’, then he said, ‘Here’s the gun, and I am the one that did it.’ ” Officer Hestand and three other officers thereupon talked with defendant for 55 minutes,1 and the conversation was tape-recorded.
At the outset of the conversation Hestand told defendant to “start from the bottom.” Defendant said he “killed the guy, and that is all. ’ ’ Hestand asked him whom he had killed, and defendant said the victim was a liquor store attendant hut he did not know the man’s name. In response to questions as to the location of the store and its name, defendant said it was on Lincoln Boulevard and was named “Mary’s.” Hestand then asked for the circumstances of the killing. Defendant said that he lived near Mary’s, so it was a “logical place to hit”; that he went into the store, asked for a pack of cigarettes, pulled out his gun, and said “this is a stick-up”; that he saw the attendant start to push a button which would notify the police; that after defendant told him not to push the button, the attendant pulled out a gun and fired; that defendant thought he was hit and shot at the clerk who fell; and that defendant then “reached over the counter and shot [the victim] some more. ’ ’
In response to ensuing questions by Hestand, defendant stated that he did not know who fired first, that his first shot hit the decedent in the temple over the right eye and another wound was in his chest (such wounds are shown by the autopsy report), and that the killing occurred either at 11:30 or 12:30 at night “a week ago last Sunday” (which was the night of the killing).
Hestand then inquired where defendant got the gun, and why he selected Mary’s to rob. Defendant said he bought the gun, and robbed Mary’s because he did not have a car and the store was near his home. Hestand asked if he had ever had an argument with decedent, and defendant said no, denied knowing decedent’s name, stated that he killed to prevent identi*352fication, and that he felt sorry for the attendant. He also said that he intended to kill the clerk after taking money from him, that the attendant’s shooting at him "threw me off,” and that he did not take any money, but only a pack of cigarettes. When asked what ammunition he used, he replied "thirty-two automatic. ”,
Further questioning dealt with details relating to the crime and information as to defendant’s background. He was asked, among other things, if he had ever been in a mental institution, whether he had any “mental trouble,” whether he had read about the crime in a newspaper, and why he was seeing a named doctor whose card was in defendant’s wallet. At one point.when asked if he felt remorseful, defendant replied, “Well, I don’t know. I can’t say that I am sorry that I killed the guy, you know, because I wanted to kill him, you know, and I had planned to kill him.” At another point, when asked about the gun battle, defendant said, “I thought that dirty son of a bitch, I will get him, you know.” At the conclusion of the conversation one of the officers asked, “Do you think we ought to get him over and get him booked?,” and another officer replied, "Okay. ’ ’
Defendant took the stand in his own behalf at the instant penalty trial 'and testified to the following effect: On the night of the crime he went to the liquor store to rob and murder whoever was there but after entering the store and talking to the clerk he realized he “couldn’t shoot him just like that.” He thinks that he and the decedent shot simultaneously. He expressed remorse for having killed the decedent and stated that he committed the murder because he had a suicidal impulse to be executed by the state.
Defendant contends that the trial court erred in admitting his tape-recorded confession over his objection based on Escobedo v. Illinois, 378 U.S. 478 [12 L.Ed.2d 977, 84 S.Ct. 1758], and People v. Dorado, 62 Cal.2d 338 [42 Cal.Rptr. 169, 398 P.2d 361] .2 We do not agree.
*353The instant penalty retrial was after the decision was rendered in Escobedo v. Illinois, supra, 378 U.S. 478, but before the decision in Miranda v. Arizona, 384 U.S. 436 [16 L.Ed.2d 694, 86 S.Ct. 1602, 10 A.L.R.3d 974], The principles enunciated in Escobedo and People v. Dorado, supra, 62 Cal.2d 338, but not those in Miranda are therefore applicable here. (Johnson v. New Jersey, 384 U.S. 719 [16 L.Ed.2d 882, 86 S.Ct. 1772]; People v. Rollins, 65 Cal.2d 681 [56 Cal.Rptr. 293, 423 P.2d 221].)
The police had no evidence connecting defendant with the crime when he voluntarily walked into the police station, admitted the killing, and produced a gun that he claimed was the murder weapon. At that time there thus appeared to be a substantial possibility that he was a mentally disturbed person or a fraud falsely confessing to the crime. It is a matter of common knowledge that many such persons have confessed to crimes which investigation develops could not have been committed by them. In the unsolved so-called “Black Dahlia” case in Los Angeles County the number of such persons ran into several hundred. In the present case the object of the 55-minute conversation clearly was not to elicit a confession but to eliminate the possibility that defendant was a mentally disturbed person or a fraud. Accordingly, there was absent one of the conditions essential to render the conversation inadmissible under Escobedo v. Illinois, supra, 378 U.S. 478, and People v. Dorado, supra, 62 Cal.2d 338.
It is true that early in the conversation defendant showed considerable familiarity with the details of the crime, such as the date and place of the killing, the fact the attendant had a gun, roughly the number of times he was shot, and the location of the wounds, but such knowledge could have been obtained from a source such as a newspaper or the actual killer, and it would not have been unreasonable for the police still to have believed that there was a substantial possibility that defendant was a mentally disturbed person or fraud. An indication that the police retained that belief after defendant *354showed his familiarity with the crime appears from their asking him questions such as whether he had ever been in a mental institution and why he was seeing the doctor whose card was in his wallet. It is apparent that in the present case the officers were not engaging in tactics of the type that in the past have spawned involuntary confessions, the evil Escobedo sought primarily to prevent (In re Lopez, 62 Cal.2d 368, 372-373 [42 Cal.Rptr. 188, 398 P.2d 380]) but rather were seeking to ascertain whether defendant’s voluntary confession was untrue.
As this court pointed out in People v. Cotter, 63 Cal.2d 386, 393, 396 [46 Cal.Rptr. 622, 405 P.2d 862] (vacated on another ground in 386 U.S. 274 [18 L.Ed.2d 43, 87 S.Ct. 824]), Escobedo and Dorado “were aimed at restraining law enforcement officers, once the accusatory stage has been reached, from the use of inquisitorial techniques in seeking to prove the charge against the accused out of his own mouth. They were never intended to discourage a defendant from volunteering to the police his complicity in the perpetration of a crime nor to prohibit the police from receiving and acting upon such confessions. . . . Neither this court, nor the United States Supreme Court, has ever taken the position that the desire of a guilty man to confess his crime should be stifled, impeded, discouraged, or hindered in any way. The contrary is true. ’ ’
A confession written by a stenotypist and signed by defendant after 4 p.m. on July 11, 1962, at the Los Angeles police headquarters where he was taken following the tape-recorded conversation was admitted over an objection based on Escobedo• and Dorado, and defendant urges that the admission of his written confession was prejudicial error. This court has held that any substantial error at a penalty trial must be deemed to be prejudicial (People v. Hines, supra, 61 Cal.2d 164, 169-170), but any error in admitting defendant’s written confession was not substantial error because that confession contained essentially the same matters appearing in Ms prior taped confession. (People v. Jacobson, 63 Cal.2d 319, 331-332 [46 Cal.Rptr. 515, 405 P.2d 555] [cert. den. 384 U.S. 1015 [16 L.Ed.2d 1036, 86 S.Ct. 1954] ] (erroneous admission of confessions at guilt and penalty trial held nonprejudieial because they were merely cumulative).) We likewise believe beyond a reasonable doubt that any error in admitting .the written confession was harmless. (Chapman v. California, 386 U.S. 18 [17 L.Ed.2d 705, 87 S.Ct. 824].)
*355Defendant also contends that the trial court erred in refusing to give a requested instruction concerning Dorado. Apart from the fact that Dorado presents a question of admissibility for the judge (see Jackson v. Denno, 378 U.S. 368, 386, fn. 13 [12 L.Ed.2d 908, 921, 84 S.Ct. 1774, 1 A.L.R.3d 1205]), the instruction did not correctly state the law because it told the jury to disregard extrajudicial statements made by defendant if he was not previously advised of his constitutional rights, without mentioning that the rule applies only after the accusatory stage has been reached.
There is no merit in defendant’s contention that the trial court erred in permitting, over his objection, psychiatric testimony to the effect that defendant might kill again under similar circumstances. Such evidence related to defendant’s mental condition and was admissible. (People v. Hines, supra, 61 Cal.2d 164,173.) Equally without merit is the claim that the prosecutor committed error in arguing to the jury along the same line. If the evidence on this matter was admissible, so was the argument.
Also without merit is defendant’s contention that we should disapprove the instruction proposed in People v. Morse, 60 Cal.2d 631, 648 [36 Cal.Rptr. 201, 388 P.2d 33], (See People v. Jacobson, supra, 63 Cal.2d 319, 332-333.)
Defendant’s next claim of error involves a challenge of the trial court judge. On October 8, 1964, the cause was called before Judge Rhodes. On that day the prosecutor moved to continue the matter until the 14th, so that the court could read the transcript of the prior penalty trial and decide from that whether it would set aside a death penalty verdict should the jury bring one in. If so, the prosecutor stated, it would be “a waste of the taxpayer’s money” to have “a full-scale trial.” On the other hand, if the court felt that it might uphold the death penalty, the trial would take place as planned. Defense counsel agreed to this, asking the court also to read certain psychiatric reports and to consider the fact that defendant would testify in the second trial, whereas he had not testified at the first. The court agreed to do so.
On October 14, the trial judge informed defense counsel that on the basis of what he had read he would not set aside a death penalty verdict were one rendered. Defense counsel then filed an “affidavit of disqualification” in which he alleged that he believed that Judge Rhodes was prejudiced against defendant and that defendant could not have a fair and impartial trial before him. At a hearing on October 15, the court denied *356the challenge and stated that the court “is impartial, unbiased, and that there exists no reason in fact why the defendant may not have a fair and impartial trial before this Court. ’ ’
Considered as a peremptory challenge made under section 170.6 of the Code of Civil Procedure, defendant’s challenge was properly denied, for it was filed too late. We recognized in McClenny v. Superior Court (1964) 60 Cal.2d 677, 683 [36 Cal.Rptr. 459, 388 P.2d 691], that “a section 170.6 motion comes too late when filed after the judge has decided preliminary contested matters.” (See also Swartzman v. Superior Court (1964) 231 Cal.App.2d 195, 200 [41 Cal.Rptr. 721], and Michaels v. Superior Court, 184 Cal.App.2d 820, 824-827 [7 Cal.Rptr. 858].)3 As stated in Jacobs v. Superior Court (1959) 53 Cal.2d 187, 191 [1 Cal.Rptr. 9, 347 P.2d 9], if the rule were otherwise, litigants could “gamble on obtaining a favorable decision from one judge, and then, if confronted with an adverse judgment, . . . disqualify him without presenting facts showing prejudice, in the hope of securing a different ruling from another judge in . . . proceedings involving substantially the same issues.” Here defendant filed his affidavit only after learning that the judge was not going to favor him on a matter which defendant agreed to submit to him. It was then too late to have the judge disqualified under section 170.6.
Defendant urges that by reading the transcript and medical reports, the trial judge “prejudged” an issue he would be required to pass upon at trial (if and when the jury returned a verdict of death) and was therefore no longer impartial and should have disqualified himself. This argument cannot be accepted. Judges frequently pass upon pretrial motions, such as demurrers and motions to dismiss, which in*357volve issues they may have to again pass upon later in the trial, as upon a motion for nonsuit or directed verdict, and a judge who passes on a pretrial motion obviously need not disqualify himself from further participation in the case.
There is no merit in defendant’s claim that the trial court erred by denying his motion to withdraw his plea of guilty. The motion was predicated on the ground that defense counsel at the time he advised defendant to enter the guilty plea believed defendant’s confessions were admissible in evidence and defendant had no defense and that subsequent changes in the law (Escobedo and Dorado) assertedly made those confessions inadmissible. As already pointed out, the tape-recorded confession was clearly admissible, and that confession admits guilt of murder in the first degree. There is no reason to believe that counsel would have advised defendant differently from the way he did had he realized that this confession was admissible but that a subsequent one might not be admissible.
Defendant filed with this court a petition in which he seeks leave to withdraw his guilty plea, or in the alternative the appointment of a referee to take testimony to determine whether his guilty plea was voluntary.4 According to the petition, he pleaded guilty, in accordance with the advice of the public defender who represented him, because the public defender told him that if he did not plead guilty he would receive the death penalty, that if he pleaded guilty he would be given a life sentence, and that “the prosecuting officials,” with whom the public defender had talked, would accept a guilty plea and “recommend a sentence of life imprisonment. ’ ’
Mere advice or assurance by defense counsel will not vitiate a plea entered in reliance thereon. (In re Teran, 65 Cal.2d 523, 528 [55 Cal.Rptr. 259, 421 P.2d 107]; People v. Reeves, 64 Cal.2d 766, 776 [51 Cal.Rptr. 691, 415 P.2d 35] ; In re Atchley, 48 Cal.2d 408, 418 [310 P.2d 15] ; People v. Toth, 224 Cal.App.2d 130, 132 [36 Cal.Rptr. 417].) Although representations by defense counsel as to a purported commitment as to penalty from a responsible state official, if the acts of such state official apparently corroborate the representation, *358where relied upon by defendant in good faith may constitute justification for permitting a withdrawal of a guilty plea (People v. Gilbert, 25 Cal.2d 422, 443 [154 P.2d 657]; see People v. Jones, 52 Cal.2d 636, 650 [343 P.2d 577]), defendant’s allegations do not show that this is such a case. Moreover, defendant has not alleged facts showing that he acted with due diligence in seeking to withdraw his guilty plea on the grounds now urged. (See In re Watkins, 64 Cal.2d 866, 870-872 [51 Cal.Rptr. 917, 415 P.2d 805]; People v. Welch, 61 Cal.2d 786, 790-791 [40 Cal.Rptr. 238, 394 P.2d 926]; People v. Quigley, 222 Cal.App.2d 694, 700 [35 Cal.Rptr. 393].) Defendant states that he has been “emotionally disturbed’’ but has not otherwise explained his apparent delay of nearly four years, during which two penalty trials have been conducted, in making the instant claim.
The petition for permission to withdraw the guilty plea or for the appointment of a referee is denied, and the judgment is affirmed.
Traynor, C. J., McComb, J., Tobriner, J., Sullivan, J., and Roth, J. pro tem.,* concurred.
The transcript discloses the following during the examination of Officer Hestand: “Q. When and where did you have your first such conversation [with defendant regarding Billy Cooper’s death] ? A. It was on July the 11th, 1962 at the Venice Detective Bureau... at about 2:30 in the afternoon. Q. Who else was present at that time? A. Sergeant Dahl, Sergeant Murphy and Officer Silvers, and I believe that was all. ’ ’
Defendant makes no eláim that the trial court failed to examine the taped confession in the light of Dorado. The dissent assumes the trial court failed to do so. Even if this assumption were correct, such failure would not be prejudicial error because the tape was properly admitted. Furthermore, the assumption is not warranted by the record. The record shows: When the judge overruled the objection to the tape, he did not state the reason for his ruling. After the tape had been played, defendant moved to strike it, and the court stated, “The motion is denied. It should be remembered that we are here concerned with penalty. The matter of the use of these confessions or admissions establishing guilt has already been determined. They are left in for the limited purpose of the issue here involved. ’ ’ Although this comment could be viewed as indicating *353the judge did not think Dorado applied to a penalty trial, the comment did not show that he denied the motion to strike, or had previously overruled the objection, solely on that ground. Thereafter, at the hearing on defendant’s motion for a new trial, which apparently was based in part on asserted error in admitting the tape, the judge raised the question whether Dorado applied to a penalty trial and then heard arguments directed both to that issue and to the issue whether the accusatory stage had been reached. When the judge denied the motion, he did not sta*-" the reason for his ruling.
In 1965 section 170.6 was amended by the addition of a provision that "The fact that a judge has presided at or acted in connection with a pretrial conference or other hearing, proceeding or motion prior to trial and not involving a determination of contested fact issues relating to the merits shall not preclude the later making of the motion provided for herein at the time and in the manner hereinbefore provided.” This provision was not in effect when the trial court ruled on defendant’s challenge in the instant case but was later enacted while his automatic appeal was pending. Section 3 of the Code of Civil Procedure provides, "Ño part of it is retroactive, unless expressly so declared.’’ (See Barry v. Barry, 124 Cal.App.2d 107, 111-113 [268 P.2d 147].) Furthermore, had the provision been in effect when the trial court ruled on defendant’s challenge, it would not have aided him because the trial judge’s decision that on the basis of what he had read he would not set aside a death penalty verdict clearly involved "a determination of contested fact issues relating to the merits.”
Defendant also requests that a referee be appointed to determine whether he was “afforded the aid of competent counsel” and whether his confessions were voluntary, but he has not alleged any facts from which it appears his attorney was incompetent or his confessions involuntary.
Assigned by the Chairman of the Judicial Council.