Hamilton, J.
The petitioner, by way of habeas corpus, seeks to have a verdict and sentence of death imposed upon him set aside. He contends that the process of selecting the jury violated his right to an impartial jury within the contemplation of the sixth and fourteenth amendments to the United States Constitution, as those amendments have been interpreted and applied by the United States Supreme Court in the cases of Witherspoon v. Illinois, 391 U.S. 510, 20 L. Ed. 2d 776, 88 S. Ct. 1770 (1968), and Boulden v. Holman, 394 U.S. 478, 22 L. Ed. 2d 433, 89 S. Ct. 1138 (1969).
Petitioner was charged in Clark County, Washington, with two counts of murder in the first degree in connection [391]*391with the brutal slaying of two minors. He entered pleas of not guilty and not guilty by reason of insanity or mental irresponsibility as to each count. Trial before a jury was held in May, 1965, and he was found not guilty by reason of insanity or mental irresponsibility on the first count and guilty on the second count. The jury recommended the death penalty with respect to the second count finding.
On appeal, this court affirmed the resultant judgment and sentence. State v. Hawkins, 70 Wn.2d 697, 425 P.2d 390 (1967), cert. denied, 390 U.S. 912, 19 L. Ed. 2d 883, 88 S. Ct. 840 (1968). Subsequently, the United States Supreme Court rendered its decision in Witherspoon v. Illinois, supra, and this petition followed.
There is no question before us as to petitioner’s guilt of the murder as charged in the second count. Our sole inquiry is directed to the question of whether, at the time of trial, prospective jurors were improperly excused for cause on voir dire examination because of their reservations concerning capital punishment.
On the morning trial commenced, a panel of 61 veniremen1 reported and assembled in the courtroom. Twelve prospective jurors were drawn and took seats in the jury box. All veniremen were then sworn and advised by the court of the charges against the defendant and his pleas thereto. Four jurors were immediately excused because of preconceived opinions concerning guilt or innocence. Upon their replacements being seated in the jury box, the trial judge, with the concurrence of the prosecuting attorney addressed the following remarks to the jury panel and to those seated in the jury box:
Ladies and gentlemen of the jury, this being a charge of first degree murder, as known under our State laws as a capital case, and the maximum punishment in such a case, if the accused is found guilty and it may be so determined by the jury, that the death penalty may be inflicted. This is known as capital punishment. Is there any member of this jury, or in the jury box, who does [392]*392not believe in, or who we’ll say believes against capital punishment?
Apparently at this point some 12 prospective jurors raised their hands, three of whom were seated in the jury box. The trial judge then directed his next remarks' to those in the jury box and the following colloquy took place:
Now this is the law of this State, and you’d feel that even though it is the law that you could not follow this law, is that correct, Mrs. Wolfenbarger? Mrs. Wolfenbarger: Yes. The Court: And Mrs. Pace, is this your belief also? Mrs. Pace: Yes. The Court: And Mr. Levanen, is this your belief, you’re opposed to capital punishment? Mr. Levanen: Yes. The Court: Do you care to interrogate further on this, Mr. Jones? Mr. Jones: No, if they’ve indicated this is a matter which for any reason they are opposed to as a matter of their policy — it is the law of this State, and of course if they could not follow the law then they would not qualify as jurors. The Court: Do you wish to interrogate Mrs. Wolfenbarger? Mr. La-Londe: No, your honor. Mr. Jones: I think she would have to be excused your honor. The Court: Mrs. Wolfen-barger may be excused. Mrs. Pace may be excused, and Mr. Levanen may be excused.
Three replacements were then drawn, one of whom, a Mrs. Helen E. Bakker, indicated reservations concerning capital punishment. At this point, and as a prelude to examining Mrs. Bakker on voir dire, the prosecuting attorney stated:
Mr. Jones: I don’t know how many of the people back here raised their hands. Mrs. Bakker, or any of you other people I wish you’d follow along. If you have because of a religious belief, or otherwise, any feeling that you could not sit on the case with an open mind that might involve this problem — that’s something of course that can’t be determined until the case has been fully presented to you.
The voir dire examination of Mrs. Bakker proceeded, as noted in the margin,2 and culminated in the following question, answer, and disposition:
[393]*393Q. Well Mrs. Bakker, let me point it up to you this way, all of us may have some differences in our minds about what the law ought to be on some subjects. It might be that they ought to put a notice on cigarettes, or not, you see, that they’re dangerous, something of this sort. Now a part of the law of the State of Washington is that capital punishment may be the punishment, but the jury decides that. You may never come to the point here —you may come to the point, but at this time we have to know if you did, whether or not withstanding your opinion as to what you think the law ought to be, whether you could objectively approach that problem of consideration in connection with the evidence as you found it to be, and the facts as you found them to be, or whether you would then not be able to go on as a juror and say, “No, I just can’t consider that.”? A. That’s right, I just don’t think I would have an objective opinion on that point. Mr. Jones: In that case, your honor, we would have no objection to excusing Mrs. Bakker. The Court: Do you, Mr. LaLonde? Mr. LaLonde: No, we have no objection. The Court: In that case we’ll excuse Mrs. Bakker. Call another juror please.
The voir dire examination thereafter proceeded through some 10 prospective jurors without further reference to capital punishment, until the name of Mrs. Susie Jenner was drawn when the following occurred:
[394]*394Mrs. Jenner: I had already expressed myself as not being in favor of capital punishment. The Court: Any objection to excusing Mrs. Jenner? Mr. Jones: No objection. Mr. LaLonde: No objection. The Court: Call another juror. Thank you. Clerk: No. 23, Russell Eplay. The Court: Pardon me, had you indicated anything about the question of capital punishment? Mr. Eplay: I don’t believe in it. The Court: I thought he had raised his hand, but I — Mr. Jones: Yes, I had made a note of Mr. Eplay. The Court: You may be excused then. Call another juror.
After 12 prospective jurors were otherwise passed for cause, the defendant through his counsel exercised 7 of his 12 peremptory challenges. During the course of the voir dire examination of the veniremen drawn as replacements, two more prospective jurors — Mr. Lee A. Hildebrand and Mrs. Louise Bakke — were excused for cause, in the following manner:
The Court: . . . Call another juror. Clerk: No. 38, Lee A. Hildebrand. Mr. Hildebrand: Your honor, I have raised my hand, I’m very much opposed to capital punishment. The Court: All right, thank you. Call another juror, please. . . . The Court: Call another juror. Clerk: No. 6, Louise Bakke. Mrs. Bakke: Your honor, I was one that was against capital punishment. The Court: Thank you. Mrs. Bakke is excused, call another juror.
A jury of 12 and 2 alternates was thereafter seated.
In summary, 35 members of the 61 member panel were drawn and examined on voir dire. Eight, or approximately 25 per cent of those drawn, were excused for cause in the manner heretofore set forth. Six were excused for cause on other grounds, and seven were peremptorily challenged by the defendant. The prosecuting attorney did not exercise any of the state’s 12 peremptory challenges. The names of the additional four members of the panel who raised their hands in response to the trial judge’s preliminary question concerning capital punishment were not drawn.
In State v. Smith, 74 Wn.2d 744, 446 P.2d 571 (1968); State v. Aiken, 75 Wn.2d 421, 452 P.2d 232 (1969); and State v. Adams, 76 Wn.2d 650, 458 P.2d 558 (1969), we [395]*395noted the holding summarized in Witherspoon v. Illinois, 391 U.S. 510, 521-22, 20 L. Ed. 2d 776, 88 S. Ct. 1770 (1968):
Specifically, we hold 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 its infliction.
Amplification of this holding is found in note 21 of the opinion, at pages 522-23, wherein the court observed:
Just as veniremen cannot be excluded for cause on the ground that they hold such views, so too they cannot be excluded for cause simply because they indicate that there are some kinds of cases in which they would refuse to recommend capital punishment. And a prospective juror cannot be expected to say in advance of trial whether he would in fact vote for the extreme penalty in the case before him. The most that can be demanded of a venireman in this regard is that he be willing to consider all of the penalties provided by state law, and that he not be irrevocably committed, before the trial has begun, to vote against the penalty of death regardless of the facts and circumstances that might emerge in the course of the proceedings. If the voir dire testimony in a given case indicates that veniremen were excluded on any broader basis than this, the death sentence cannot be carried out even if applicable statutory or case law in the relevant jurisdiction would appear to support only a narrower ground of exclusion. . . .
We repeat, however, that nothing we say today bears upon the power of a State to execute a defendant sentenced to death by a jury from which the only veniremen who were in fact excluded for cause were those who made unmistakably clear (1) that they would automatically vote against the imposition of capital punishment without regard to any evidence that might be developed at the trial of the case before them, or (2) that their attitude toward the death penalty would prevent them from making an impartial decision as to the defendant’s guilt. Nor does the decision in this case affect the validity of any sentence other than one of death. Nor, finally, does today’s holding render invalid the conviction, as opposed to the sentence, in this or any other case.
[396]*396By way of further elucidation and in stressing the need for clarity in this area of the voir dire examination of prospective jurors, the court pointed out in note 9 of the opinion, at page 516:
Unless a venireman states unambiguously that he would automatically vote against the imposition of capital punishment no matter what the trial might reveal, it simply cannot be assumed that that is his position.
The underlying theme of Witherspoon, as we read it, is that citizens who entertain reservations about capital punishment, but who nonetheless can subordinate their personal views to their obligation as a juror and weigh the penalty issue in a proper case, constitute a significant segment of the community within the concept that a jury shall be drawn from a cross-section of the community. It follows from this, in the eyes of Witherspoon, that a systematic and indiscriminate exclusion for cause of such citizens from jury service in a capital case violates a defendant’s constitutional right to a fair, impartial, and representative jury upon the issue of penalty. If, then, prospective jurors are to be challenged and excused for cause because of their views concerning capital punishment, it is essential that the basis of their disqualification be clearly established upon the voir dire examination, and preserved in the record for appellate review.
Measured against the thesis and the rather rigid requirements of Witherspoon, we are satisfied that the voir dire examination we have referred to above does not make it unambiguously and unmistakably clear that the eight prospective jurors excused for cause because of their views on capital punishment were excused because they would irrevocably and automatically vote against the death penalty regardless of what the evidence at trial might reveal.
In no instance, with the possible exception of Mrs. Bak-ker the fourth juror to be excused, were the depths or dimensions of a prospective juror’s feelings concerning capital punishment adequately explored. The first three were excused after indicating generally they could not follow “this law,” against the backdrop of a rather terse and some[397]*397what vague explanation of a juror’s duties in a capital case, coupled to a general question as to who among the panel “does not believe in, or who we’ll say believes against capital punishment.” The last four were excused without further questioning simply because they said either they were not in favor of capital punishment (Mrs. Jenner), did not believe in it (Mr. Eplay), were very much opposed to it (Mr. Hildebrand), or were against it (Mrs. Louise Bakke). And, in Mrs. Helen E. Bakker’s voir dire examination, it remains ambiguous as to whether she was excused because she could not be “objective” about capital punishment or because her beliefs were so deep-seated that she could not consider the issue. The overall tone and pattern set by the disqualification of these prospective jurors for cause, based upon their general responses to the questions asked, virtually savor of a systematic exclusion.
In State v. Aiken, supra, after noting that our prior decisions in this field of challenges for cause were in harmony with Witherspoon v. Illinois, 391 U.S. 510, 20 L. Ed. 2d 776, 88 S. Ct. 1770 (1968), we observed that, in meeting the demands of Witherspoon, as well as our prior holdings, it was not necessary to engage in a formulistic dialogue with a prospective juror on voir dire examination. Nevertheless, we endeavored to emphasize the proposition that before a prospective juror is disqualified for cause due to his beliefs with regard to capital punishment, it is essential that such dialogue as is carried on in this respect be sufficient in depth and/or in a context as will unequivocally and unmistakably establish that the prospective juror’s opposition to the death penalty is in fact such as would preclude him from imposing that penalty under any circumstances, or would prevent him from making an impartial determination upon the issue of guilt. Anything short of this cannot be squared with Witherspoon.
This was not done in the instant case, and we are compelled to the conclusion that the eight jurors in question were improperly excused for cause to the detriment of defendant’s constitutional rights as enunciated by the United States Supreme Court in Witherspoon and Boulden [398]*398v. Holman, 394 U.S. 478, 22 L. Ed. 2d 433, 89 S. Ct. 1138 (1969).
The state contends, however, that because the prosecuting attorney did not utilize any peremptory challenges it can be assumed that these jurors would have been so challenged and excused had the trial judge declined to excuse them for cause; hence, the defendant was not prejudiced. In this respect the state points to State v. Mathis, 52 N.J. 238, 245 A.2d 20 (1968). Chief Justice Weintraub, speaking for the New Jersey Supreme Court in the cited case, characterized such a contention as “relevant makeweight,” and added it to a finding by the court that the prospective jurors excused in that case had been properly questioned and disqualified. We too believe the argument to be relevant makeweight, under appropriate circumstances; however, it is fraught with too many speculative factors to constitute the sole basis upon which to justify noncompliance with the thesis of Witherspoon.
Next, the state asserts that the duty rested upon the defendant to probe the prospective jurors’ beliefs 'and to object to their excusal if they were properly qualified, and his failure so to do negates a denial of due process. Under the circumstances here present, we cannot agree with the state’s argument. In the first place, the prospective jurors were excused for cause at the state’s behest, and it was the state’s obligation to lay the proper grounds for their disqualification. This was not done, and it was not up to the defendant to shore up the state’s challenge or to interrogate them for the purpose of requalifying them. And, in the second place, the trial in this cause was conducted prior to the dissemination of the Witherspoon decision, and all trial counsel and all trial judges were not fully aware of the grave constitutional implications imported by Witherspoon into the disqualification of prospective jurors on the grounds of conscientious scruples regarding capital punishment. This being the situation, we cannot concur in the argument that the defendant’s failure to interrogate the prospective jurors and object to their dismissal negates the [399]*399constitutional guarantees retroactively afforded him by Witherspoon. Cf. Boulden v. Holman, supra.
Finally, and alternatively, the state asks that the cause be remanded for an evidentiary hearing upon the question of whether the excused jurors entertained views at the time of trial consistent with a proper disqualification. The state cites no precedent for such a procedure, and we seriously question the efficacy and reliability of such a hearing at this late date. Approximately 5 years have elapsed since the events in issue occurred and, aside from the fact that counsel in oral argument indicated that not all eight of the jurors involved were presently available, it is doubtful that those who are available could fairly and accurately recall and relate what their views on capital punishment actually were on the date of their voir dire examination. Certainly it is possible, if not probable, that their views have changed in one form or another in the meantime, and their testimony on the question now could easily, though perhaps not consciously, be influenced by such a change in their attitude.
We find no merit in this request.
In conclusion, upon this facet of the case, it is our view that Witherspoon compels the vacation of the sentence of death heretofore imposed upon the defendant, and that the cause be remanded for a new trial upon the issue of penalty. The finding of guilt and the degree of the crime stands.
In view of the fact that this disposition of the cause projects a separate trial upon the issue of penalty only, we deem it appropriate to comment briefly upon the authority therefor and the procedural aspects thereof.
Although the legislature has not specifically erected a statutory framework for bifurcated trials as such, it has, in connection with murder charges, sanctioned a trial limited to the determination of the degree and the punishment, where the accused pleads guilty to such a charge. RCW 10.49.010; State v. Davis, 6 Wn.2d 696, 108 P.2d 641 (1940). The legislature by that statute implicitly recognized that, in an appropriate case, there could be a jury trial upon the [400]*400issue of punishment alone. State v. Todd, 78 Wn.2d 362, 474 P.2d 542 (1970). We believe this to be such a case.
We have carefully perused the provisions of the proposed draft of the Model Penal Code submitted to the American Law Institute and the statutes of the State of California (Cal. Penal Code § 190.1 (West Cum. Supp. 1968)) and New York (N.Y. Penal Law § 125.35 (McKinney 1967)) as they relate to separate jury trials concerning the issue of punishment in capital cases. Though we recognize that these references are not controlling in this state, nevertheless they do project what appear to be presently acceptable and reasonable, although general, guidelines concerning the scope of the evidence adducible at a penalty hearing. See also 40 Am. Jur. 2d § 555.
In essence, and drawing upon the foregoing sources for guidance, we hold that at a separate penalty hearing, such as here ordered, relevant evidence may be presented concerning the nature and circumstances surrounding the offense involved, the defendant’s background and history, and any facts or circumstances in aggravation or mitigation of the crime and the penalty. The evidence must, however, be competent, not unduly prejudicial or inflammatory, and cannot be directed solely to impeachment of the prior adjudication of guilt.
Evidence regarding the probability of early parole or the possibility of intervention by executive clemency shall not be admitted. State v. Todd, supra. Likewise, evidence concerning the deterrent effect of one form of penalty as opposed to another shall not be received. People v. Love, 56 Cal. 2d 720, 366 P.2d 33, 809, 16 Cal. Rptr. 777, 17 Cal. Rptr. 481 (1961); People v. Kidd, 56 Cal. 2d 759, 366 P.2d 49, 16 Cal. Rptr. 793 (1961); People v. Ketchel, 59 Cal. 2d 503, 381 P.2d 394, 30 Cal. Rptr. 538 (1963).
The state will be permitted to proceed with its evidence first in order and thereafter will be limited to rebutting any new matter introduced by the defendant. The defendant may but need not take the stand on his own behalf. Final summations to the jury shall be presented in the same sequence as the order of proof.
[401]*401The jury, by appropriate instructions, shall be informed that in this state the penalty for the crime of murder in the first degree is life imprisonment, unless the jury determines that the punishment shall be death; that imposition of the death penalty in the case before it lies within the conscience and sound discretion of the jury; that in arriving at its determination upon the penalty issue, the jury shall weigh and evaluate all of the evidence presented to it bearing upon the nature and circumstances surrounding the crime, the defendant’s background and history, and the facts or circumstances in aggravation or mitigation of the crime and the punishment; that based upon such evidence the jury in arriving at its decision is entitled to consider the nature of the crime involved, the defendant’s guilt thereof, his potential for reformation and rehabilitation, society’s need for protection from his future behavior, and the furtherance of the interests of justice; and that the maximum penalty shall not be invoked in a spirit of vengeance or inflicted solely to exact retribution.
The special verdict form submitted to the jury shall be so phrased as to require an affirmative recommendation of the death penalty and the jury’s verdict in this respect must be unanimous. In the event the jury is unable to agree upon the issue of penalty, the trial court shall discharge the jury and impose a sentence of life imprisonment.
The cause is accordingly remanded to the Superior Court for Clark County for further proceedings consistent with this opinion; provided, however, the state, for good cause shown and subject to approval of the superior court, may elect to forego further proceedings, in which event a sentence of life imprisonment shall be imposed.
Finley, Rosellini, Neill, and McGovern, JJ., concur.