This appeal is from a judgment of the United States District Court for the Eastern District of Pennsylvania, sitting en banc, dismissing a petition for habeas corpus filed on behalf of Smith, the relator. Smith’s case has had a long history. It was considered by three judges of the Court of Oyer and Terminer of Philadelphia County. It has been twice to the Supreme Court of Pennsylvania, once to the Supreme Court of the United States, twice to the District Court for the Eastern District of Pennsylvania and twice to this Court. The history is fully written in opinions which have come down during the course of the various proceedings concerning Smith.1 We shall, therefore, state, *543from point to point, only such facts as are necessary to bring out the questions involved.
The case starts with a killing. Smith while a passenger in a taxi cab drew a gun and killed the taxi driver. He was almost immediately apprehended. He has been adjudged guilty of murder in the first degree and sentenced to death. The killing of the taxi driver by Smith is not denied. This is not a case where a man has been forced into a confession. Nor is it a case where a friendless man has been overreached because he did not have legal counsel. The long record shows that Smith’s claimed rights have been vigorously and intelligently asserted. The questions turn upon events in the course of Smith’s trial which will be stated as the points arising out of them are taken up.
Federal and State Jurisdiction
First be it noted that Smith was not prosecuted by the United States; he was accused, tried and convicted in the Pennsylvania courts. Citations of federal decisions like Frame v. Hudspeth, 10 Cir., 1939, 109 F.2d 356, are of no value to us unless they raise the same constitutional law points present when habeas corpus is sought for a state prisoner. Smith’s case went once to the Supreme Court of Pennsylvania on the question of a sentence imposed by the Court of Oyer and Terminer. It was again before the Supreme Court of Pennsylvania in ha-beas corpus proceedings. The basis for the prayer for the writ was the same as that now before the federal courts. The Supreme Court of Pennsylvania denied the writ and certiorari was denied by the Supreme Court of the United States.
So every question before us has been decided adversely to Smith’s contentions and the Supreme Court has refused review through certiorari. What is the significance of such refusal? It is urged upon us by the respondent that it is highly significant. He argues that if Smith’s petition for certiorari had shown a deprivation of constitutional rights his case would have been reviewed. That certiorari was refused shows, it is argued, that no such deprivation was even alleged. There was, it is pointed out, no such direction by the Supreme Court as there was in Burke v. State of Georgia, 1950, 338 U.S. 941, 70 S. Ct. 422, 94 L.Ed. 580, allowing petitioner to proceed in the federal district court without prejudice from the denial of his petition for certiorari.
The last word on the subject by the Supreme Court is Darr v. Burford, 1950, 339 U.S. 200, 70 S.Ct. 587, 94 L.Ed. 761 2 The proposition decided in that case does not immediately concern us here. If application for certiorari must in every case be made to review the final state court action before resort may be had to habeas corpus in a federal court, that condition has been fulfilled. Our narrower question is: What effect in the lower federal courts is to be given to the denial of certiorari by the Supreme Court? The Court, through Mr. Justice Reed, says, 339 U.S. at 217, 70 S.Ct. at page 597, 94 L.Ed. 761: “It is this Court’s conviction that orderly federal procedure under our dual system of government demands that the state’s highest courts should ordinarily be subject to reversal only by this Court and that a state’s system for the administration of justice should be condemned as constitutionally inadequate only by this Court.”
The doubt-creating word is “ordinarily.” When should a district court and a court of appeals again examine merits? Our inclination would naturally be to say “never.” It is highly uncomfortable for those of us in courts not of last resort to sit in what is, in effect, review of the highest court of a state. The responsibility is one from which we should be glad to be relieved. But Darr v. Burford does not say that denial of certiorari relieves us. The dissenting opinion in that case points out that no directions are given the lower federal courts on the point. It would be unseemly for us to make argument either way on the questions upon which our superiors *544differ.3 We think that what we clearly must do, until we are told to the contrary, is to follow the well established rule that a denial of certiorari does not prove anything except that certiorari was denied. When the applicant for habeas corpus has petitioned for certiorari he has fulfilled a procedural requirement. If he gets certio-rari his constitutional questions will be adjudicated on the merits by the Supreme’ Court. If he does not, he may apply to the appropriate lower federal court for a writ. This seems to be the rule compelled, if not decided, by Darr v. Burford and considerations expressed therein.4
But it is to be reiterated that we are not an appellate court for the correction of errors under state law. Each point raised by the relator is to be tested by whether it alleges a violation of rights under the United States Constitution: nothing more. That these allegations have been decided on the merits by the highest state court is a fact to be given great weight by a district court in passing upon petitions for habeas corpus. But that fact does not relieve the federal court of the duty to pass upon the merits of the petition.
The District Court exercised its “discretion” to decline to pass upon the merits. We do not think it had such discretion, and proceed to consider whether, if factually true, the petition sets forth a violation of the federal Constitution.
Does Relator’s Petition Allege Violation of Due Process?
Smith’s points have to do with (1) whether his mental state was such that he could be tried; (2) whether his. mental state at the time of th^ shooting was such that he could be convicted of murder.
Has a man a constitutionái right not to be tried or executed if “insane” or not to meet the penalty for a crime committed while in that condition? Is the imposition of criminal responsibility in such case, ’in. the words of Mr. Justice Black, so “offensive to the fundamental principles of liberty and justice which lie at the base of all our civil and political institutions” that it violates substantive due process?5 We do not know. It may be no violation of the federal Constitution for a state to provide by law that insanity at the time of commission of a crime no longer bars conviction, sentence or execution. The same may be true as to mental incompetence at the time of trial, sentence or execution.6 We are not called upon to decide these questions.
The reason we are not called upon to decide them is that Pennsylvania does not disregard the mental condition of a defendant accused of crime. According to its substantive law a man has the right not to stand trial or pay the penalty for an act if his mental condition is not such as to fulfill the legal test of “sanity.” 7 And it recog-, nizes the familiar rule that insanity at the time of the offense requires acquittal.8 Smith is entitled to have procedural due process observed in the protection of these substantive rights even though substantive due process would not compel the rights to be given. Insanity being a defense under Pennsylvania law, due process guarantees all defendants fair opportunity to present the defense. So we must examine the contentions on which Smith relies for his charge that Pennsylvania subjected him to treatment which was not due process of law.
*545The first is that he was overreached” when he was arraigned. Prior to arraignment Smith had been confined in jail. The day before arraignment his relatives had procured private counsel for him. That counsel had not yet had opportunity to enter his appearance and knew nothing of the time set for Smith’s arraignment. So when the prisoner stood up to plead he was alone, and the court suggested that Joseph Ales-sandroni, Esq.,, a member of the Philadelphia Bar in good standing who was in the courtroom at the time, stand with him. Mr. Alessandroni did not know Smith and had but a moment’s consultation with him. Smith, on Mr. Alessandroni’s advice, pleaded not guilty.
Did this arraignment constitute lack of due process? It is a little hard to see how entering a plea of not guilty can deprive a man of any rights. In the cases holding that the Fourteenth Amendment required' effective assistance of counsel at arraignment a plea of guilty had been entered.9 The possibility of prejudice in such cases is obvious. But it is argued here that because counsel was not, and had no opportunity to be, informed of Smith’s previous mental history he could not at the time of arraignment ask for a special trial to test his sanity then and there, as provided by Pennsylvania law.10 Lack of effective assistance of counsel resulted in the loss of this valuable right, says relator, and such loss is lack of due process of law.
The argument exaggerates the importance of rights under the statute relied on. Whether a hearing on mental condition in limine will he granted rests in the sound discretion of the judge under Pennsylvania law. The discretion is reviewable, but is so broad that the judge may refuse even to hear evidence on the point. Webber v. Commonwealth, 1888, 119 Pa. 223, 13 A. 427. The most Smith lost, therefore, was the chance to have the judge before whom he was arraigned exercise this broad discretion whether to grant a trial in limine on the question of sanity at the time.
We conclude that the loss of such an opportunity was not so prejudicial to defendant as to amount to violation of due process. Due process does not go so far as to require a hearing on mental condition, in any particular manner or at any particular stage in the proceedings. Certainly it does not require a hearing in limine on the question as counsel for relator contend. The most that it requires, in our view, is an opportunity to have adequate hearing on the question before guilt is finally determined. Under Pennsylvania law defendant still had the right to submit the question of his mental capacity to stand trial to the jury which would try the indictment.11 Pennsylvania provides also a means for special inquiry into an accused’s mental condition both while defendant is in custody awaiting trial12 and upon his appearance in *546court.13 The question of defendant’s mental ability to stand trial remained open and could have been raised in several different ways after arraignment. We conclude, therefore, that even if Pennsylvania did not provide defendant with “effective assistance of counsel” at his arraignment, he suffered no deprivation of federal constitutional right because of it.
Following Smith’s arraignment his trial was postponed several times at the request of his lawyer. The latter wanted to get from New York material relative to Smith’s hospitalization in a mental institution there. Upon the statement of Smith’s privately retained counsel that no money was available to procure such information, the court appointed him and another attorney as state-appointed counsel for Smith. This made it possible to subpoena the records and witnesses from New York, a matter which took some time. In the meantime, after consultation among the assistant district attorney in charge of the case, defendant’s lawyers and, in part at least, the trial judge, the plea of not guilty was withdrawn and the plea of guilty entered. A hearing was had September 21, 1948, in which the Commonwealth’s evidence was introduced, it being agreed that further hearings would be had at which defendant could produce his evidence.
On October 28, 1948, a second hearing was had at which defendant introduced records from the New York hospital and testimony of several doctors who had examined Smith there, as well as records from the Philadelphia General Hospital. This evidence revealed that in 1945 Smith had been committed to an institution in New York by order of a New York court subsequent to a mental examination and report. At this institution his condition was diagnosed as dementia praecox, and he remained there for four months before being discharged as-recovered. It also appeared that at one time Smith had voluntarily committed himself to the Philadelphia General Hospital because he was afraid he was going to kill someone, but was released after ten days.
After the hearing of October 28 the court appointed a psychiatrist, Dr. William Dray-ton, Jr.14 to examine Smith. Dr. Drayton did so and at a hearing on November 5, 1948, reported his findings and was subjected to questioning by the district attorney, the court and by Smith’s lawyers. Dr. Drayton’s expressed view was that the prisoner was perfectly sane both at the time of the killing and at the time he examined him, and was “faking” for the purpose of avoiding trial. The trial court concluded that Smith was sane both at the time of trial and at the time he killed the taxi driver and entered a judgment of guilty in the first degree and fixed the penalty at execution by electrocution.
On behalf of Smith it is said that it is lack of due process of law to fail to provide a psychiatrist at public expense to assist defense lawyers in a case which involves a question of an indigent prisoner’s sanity. The prosecution may have such psychiatric *547consultation, it is said, “to prove the relator is sane.” Fundamental fairness, the argument runs, requires the same privilege to be given to the defendant at public expense if he cannot pay for it himself. There is nothing in the record to indicate that a request for such help was ever made. Assume however that it was, as relator claims.
There is a fallacy, we believe, in the assumption that the psychiatrist was called upon by the court to prove Smith sane. He was called upon by the court at the suggestion of Smith’s lawyers, to give the court the benefit of his professional opinion, and he did. After he made his report in open court he was fully cross-examined. The doctor was not a “prosecution” witness; he was the court’s witness. This important consideration was pointed out by the First Circuit recently in a case practically on all fours with this issue of the case at bar. In that case, McGarty v. O’Brien, 1 Cir., 1951, 188 F.2d 151, 155, the court said: “The doctors designated by the Department of Mental Health to make the examination are not partisans of the prosecution, though their fee is paid by the state, any more than is assigned counsel for the defense beholden to the prosecution merely because he is, as here, compensated by the state. Each is given a purely professional job to do — counsel to represent the defendant to the best of his ability, the designated psychiatrists impartially to examine into and report upon the mental condition of accused.”
Furthermore, we . have great difficulty in accepting as a proposition of constitutional law that one accused of crime is entitled to receive at public expense all the collateral assistance needed to make his defense. Here Smith was, at public expense, given two thoroughly competent lawyers. The same argument that would entitle them to psychiatric consultation would entitle them to consultation with ballistic experts, chemists, engineers, biologists, or any type of expert whose help in a particular case might be relevant. We do not think the requirements of due process go so far. In any event, Smith had here the benefit of the past medical history and whatever further examination his lawyers cared to make of Dr. Drayton in open court. Whether the Doctor’s opinion was accurate scientifically, whether it was reached after sufficient examination, these and other questions going to the weight of the evidence are surely not before us in a habeas corpus proceeding.
Our conclusion on this issue is in accord with that reached recently by the First Circuit in McGarty v. O’Brien, quoted from above. In that case the indigent defendant’s mental condition in a capital case had been put in issue. He was examined by two psychiatrists acting in behalf of the Massachusetts Department of Mental Health pursuant to a statute. The psychiatrists reported that defendant had a psycopathic personality but was “not suffering from any mental disease or defect which would affect his criminal responsibility.” Defendant’s counsel then requested that he be allowed to employ two psychiatrists at the expense of the Commonwealth to aid in the defense. The request was denied. The Court of Appeals affirmed the District Court decision on habeas corpus that this did not constitute denial of due process. It said “ * * * examination and report by two competent and impartial experts supplied at state expense is enough, we think, to satisfy the state’s constitutional obligation under the due process clause.” McGarty v. O’Brien, supra, 188 F.2d at 157.
We agree. The only difference between what Massachusetts did in the McGarty case and what Pennsylvania has done here is that in Massachusetts two psychiatrists examined defendant instead of one and they were appointed by an independent agency rather than by the court. Such a difference does not amount to the granting, of due process in one and its denial in the other.
In connection with the adjourned hearings mentioned above, there is one point made by the relator which has caused us serious concern. It is said that a court of three judges convened to hear the testimony after a plea of guilty, made their adjudication of first degree murder before they heard Smith’s evidence and that any evidence heard thereafter was considered only in mitigation in determining *548whether the penalty should he life imprisonment or death. There are some docket entries, endorsements on the indictment, of which we have been furnished a facsimile, and remarks by the Supreme Court of Pennsylvania15 indicating that as a matter of dates somebody, at least, thought this was so. From this comes the argument that the prisoner’s guilt of first degree murder was settled by the judges before his evidence was ever presented, and that he never had opportunity to have the question of his sanity, for purposes of guilt or ability to stand trial, considered.
The argument has been carefully considered with the conclusion that it is invalid. If the testimony produced on behalf of the prisoner had been such as to create doubt of his guilt he could have moved to withdraw the plea of guilty and enter a plea of not guilty.16 Action on such a motion would have been reviewable in Pennsylvania.17 We understand also that the judge can order the withdrawal of the guilty plea of - his own motion ‘and direct that the plea of not guilty be entered. There is no indication that any s-uch motion or suggestion was ever made on behalf of the prisoner. Nevertheless, the question of his guilt or lack of it was open in the trial court until the judgment of guilty was entered and penalty fixed. The latter, at least, was not until February 4, 1949. Whether the docket entries reflect -accurately the status of the case or not we see no reason to think that Smith was precluded from having his whole case considered by the three judges who constituted the trial court. It was so considered, as is shown below.
The petition for habeas corpus states that when the guilty plea was entered Smith’s counsel, the district attorney and the court agreed that if the New York records “raised an issue or doubt of Relator’s sanity, the court would consider withdrawal of the plea of ‘Guilty’.” During the course of the hearing at which such evidence was heard the following statement was made by one of the judges:
“Judge Carroll: Don’t you see what he is doing; he is helping you to prepare your resistance of this when the trial of this case comes, which may not come, 'when this plea will have to be withdrawn and the defendant will have to be tried.”' Later on, after the director of the hospital in New York who had authorized Smith’s release verified the diagnosis of dementia praecox and stated that at the time of release Smith had recovered from any mental illness which he had, the following colloquy ensued :
“Mr. Levin [counsel for defendant]: Shall I proceed to examine him further in the -face of that statement? Does that satisfy any uncertainty which your Honors may have had in regard to the withdrawal of the plea?
“Judge Guerin: It does not to my idea.
“Mr. Levin: I think it raises an issue, sir.
“Judge Sloane; I am certainly of the opinion now he was- sane and lucid in October of 1945.. * * * ”
At the last hearing the psychiatrist, Dr. Drayton, was asked by the court whether in his opinion Smith was sane, knew the difference between right and wrong, knew the nature of his acts at the time of the killing and at the time he was examined. These questions and the excerpts quoted above, together with the agreement under which the guilty plea was accepted, make it clear to us, without need of further evidence, that the questions of guilt and ability to stand trial were still open during the receipt of defendant’s evidence relative to mental condition. The principal purpose of the evi*549dence may have been to aid the court in determining penalty, but it was obviously considered on the merits of the whole case as well. A reading of the unpublished opinion of the trial court substantiates our conclusion. It discloses that the court determined that Smith was sane both when he killed the cab driver and when he was tried. That being so the only conclusion possible for the court to draw was guilt of first degree murder. The record does not disclose any motion to withdraw the plea of guilty, but if such a request was made, its refusal under these conditions presents nothing for the consideration of a federal court.
Argument on behalf of the relator suggests that the Supreme Court of Pennsylvania violated due process by considering evidence which was not before it in disposing of the habeas corpus petition. This evidence consisted of the testimony taken in the first habeas corpus proceeding in the District Court for the Eastern District of Pennsylvania. This proceeding terminated before the habeas corpus proceeding in the Supreme Court of Pennsylvania and the petition was dismissed because the relator at the time was outside the territorial limits of the Eastern District. Relator’s argument was that the Supreme Court of Pennsylvania pulled some of this testimony into its consideration gratuitously and it is denied that it was done either with agreement or acquiescence of relator’s counsel. But in the very petition to the Supreme Court of Pennsylvania for habeas corpus petitioner refers to this proceeding and gives his version of what the testimony established. We think it can hardly be lack of due process for the Supreme Court to’ refer to the testimony when the relator himself did so.
A reading of all the. exhibits indicates that this prisoner has received careful treatment at the hands of the Pennsylvania courts in the protection of his constitutional rights. His trial was postponed several times in order that his counsel might get the out-of-state records and testimony already referred to. At every step of the way he has had legal counsel. He was examined by an apparently impartial and qualified psychiatrist appointed by the court at the suggestion of his own counsel. The three judges who sat on his case in the first instance joined in an opinion a substantial portion of which was devoted to Smith’s mental condition. The Supreme Court of Pennsylvania affirmed the original judgment; it also went through the case at length upon the petition for habeas corpus.
An inquiry was made into relator’s sanity; testimony by an apparently qualified and impartial expert was received upon the point and, as pointed out above, cross-examination had. We find nothing which constitutes a lack of due process of law on the basis of anything which appears in the record before us or what the relator charges.
The judgment of the District Court will be affirmed.
. Conviction — Commonwealth v. Smith, Philadelphia, Oyer and Terminer, opinion filed March 4, 1949 (unreported), affirmed 362. Pa. 222, 66 A.2d 764 (1949). Habeas Corpus — United States ex rel. Smith v. Warden, D.C.E.D.Pa.1949, 87 F.Supp. 339 (dismissed for lack of jurisdiction), affirmed 3 Cir., 1950, 181 F.2d 847; Commonwealth ex rel. Smith v. Ashe, 1950, 364 Pa. 93, 71 A.2d 107, certiorari denied 1950, 340 U.S. 812, 71 S. Ct. 40, 95 L.Ed. 597; United States ex-rel Smith v. Baldi, D.C.E.D.Pa.1951, 96 F.Supp. 100.
. Gusik v. Schilder, 1959, 340 U.S. 128, 71 S.Ct. 149, 93 L.Ed. 146, involved a court-martial conviction. Cf. also Dowd v. United States ex rel. Cook, 1951, 340 U. S. 206, 71 S.Ct. 262, 95 L.Ed. 215.
. Compare the majority, concurring and dissenting opinions in Darr v. Burford, supra.
. The two concurring Justices and three dissenting Justices in Darr v. Burford agreed that denial of certiorari means nothing on the merits. Dictum joined in by a majority of the Supreme Court is the best available authority. We see no advantage, therefore, in citation and discussion of the great number of cases on the point. However, cf. United States ex rel. Auld v. Warden, 3 Cir., 1951, 187 F.2d 615; McGarty v. O’Brien, 1 Cir., 1951, 188 F.2d 151.
. See Phyle v. Duffy, 1948, 334 U.S. 431, 439, 68 S.Ct. 1131, 1134, 92 L.Ed. 1494.
. See Solesbee v. Balkcom, 1950, 339 U.S. 9, 70 S.Ct. 457, 94 L.Ed. 604.
. Commonwealth v. Ragone, 1935, 317 Pa. 113, 176 A. 454.
. 19 Purdon’s Pa.Stat.Ann. § 1351; Commonwealth ex rel. Smith v. Ashe, supra note 1.
. See, e.g. De Meerleer v. People of State of Michigan, 1947, 329 U.S. 663, 67 S.Ct. 596, 91 L.Ed. 584; Carter v. People of State of Illinois, 1946, 329 U.S. 173, 67 S.Ct. 216, 91 L.Ed. 172; Williams v. Kaiser, 1945, 323 U.S. 471, 65 S.Ct. 363, 89 L.Ed. 398. Cf. Council v. Clemmer, 1949, 85 U.S.App.D.C. 74, 177 F.2d 22, certiorari denied 1949, 338 U.S. 880, 70 S.Ct, 150, 94 L.Ed. 540.
; “The same [commitment] proceedings may be had, if any person indicted for an offense shall, upon arraignment, be found to be a lunatic, by a jury lawfully impanelled for the purpose * * Act of March 31, 1860, P.L. 427, § 67, 19 Purdon’s Pa.Stat.Ann. § 1352.
. Webber v. Commonwealth, supra; 19 Purdon’s Pa.Stat.Ann. § 1352.
. Tbe Mental Health Act of 1923, as amended May 28, 1937, P.L. 973, § 1, 50 Purdon’s Pa.Stat.Ann. § 48 provides in pertinent part; “When any person detained in any prison * * * whether awaiting trial or undergoing sentence, or detained for any other reason * * * shall, in tbe opinion of the superintendent, jail physician, warden [etc.] * * * be insane, or in such condition as to make it necessary that he be cared for in a hospital for mental'diseases, the said superintendent * * * shall immediately make application * * * to a law judge * * * for commitment of said person to a proper hospital for mental diseases. The said judge shall forthwith order an inquiry by two qualified physicians, or by a commission * * * [of two doctors and a lawyer, who shall *546report their findings to the judge]. The said judge may, in his discretion, summon other witnesses and secure further evidence. If he is then satisfied that the person * * * is in fact insane, he shall order the transfer of such person to a hospital for mental diseases. ”
Eelator’s counsel applied to the court for the appointment of such a Commismission but it was denied because only the warden may make such application. See Commonwealth v. Barnes, 1924, 280 Pa. 351, 124 A. 636. The warden refused to apply for it. Such refusal is reviewable by mandamus. See Commonwealth ex rel. Smith v. Ashe, 1950, 364 Pa. 93, 116, 71 A,2d 107, 119, certiorari denied 1950, 340 U.S. 812, 71 S.Ct. 40, 95 L.Ed. 597.
. 50 Purdon’s Pa.Stat.Ann. § 48, supra, continues: “When, on the production or appearance of any person charged with criminal offense, * * * it shall appear to the court that such person is insane, or in such condition as to make it necessary that he be observed or cared for in a hospital for mental diseases, proceedings for the commitment of such person to such a hospital shall be had * * * upon application of some person to be designated by the court.” This provision appears to have been disregarded or overlooked by counsel.
. Chief of the Philadelphia General Hospital psychiatric department since 1926; neuropsychiatrist in the Philadelphia Municipal Court since 1922; associate professor neuropsychiatry in the Graduate School of Medicine of the University of Pennsylvania.
. Common-wealth v. Smith, 1949, 362 Pa. 222, 223, 66 A.2d 764.
. Commonwealth ex rel. Smith v. Ashe, 1950, 364 Pa. 93, 113, 71 A.2d 107, 117; Commonwealth v. Shawell, 1937, 325 Pa. 497, 191 A. 17. Cf. 19 Purdon’s Pa. Stat.Ann. § 241. “[A person accused of crime other than homicide may waive indictment by a grand jury and plead guilty or not guilty to a district attorney’s indictment.] * * * and provided further, That the defendant may withdraw his plea of guilty, at any time before sentence, by leave of the court.”
. See note 16, supra. Cf. Commonwealth ex rel. O’Niel v. Ashe, 1940, 337 Pa. 230, 10 A.2d 404.