This petition for a writ of error relates to the 1955 convictions considered by this court in
Commonwealth
v.
Devlin,
On April 29, 1963, the Supreme Court in
White
v.
Maryland,
On November 13, 1968, the petitioner filed this petition for writ of error in which he alleges that the admission of Arsenault’s guilty plea at their joint trial deprived him of a fair trial and violated his constitutional right to confront witnesses against him guaranteed by both the Sixth Amendment to the United States Constitution and art. 12 of the Massachusetts Declaration of Rights. On October 7, 1972, a single justice of this court reserved and reported the case without decision on the petition, the assignments of error, the Superior Court return, the respondent’s answer, the stipulation of facts, and the trial transcript of
Commonwealth
v.
Devlin,
Before reaching the substantive merits of the petitioner’s claims, we must first decide whether the issues raised in this petition can be presented by a writ of error. The Commonwealth argues that LeBlanc’s failure during the trial to object to the admission of Chief Purcell’s testimony that Arsenault had pleaded guilty in Newton District Court to Merrill Lovinger’s murder and the petitioner’s subsequent failure to press this issue on direct appeal to this court prevent him from raising this claim years later in a writ of error.
The Commonwealth relies on
Cortellesso
v.
Commonwealth,
However, we hold that the
Cortellesso
rule does not bar the petitioner from raising claims whose constitutional significance was not established until after the petition
*174
er’s trial and appeal to this court. Moreover, in light of the Supreme Court’s decision to reverse the codefendant’s conviction because of the improper admission in evidence of his guilty plea at a prior hearing, we must reach the merits of the petitioner’s claim to insure that there has been no substantial miscarriage of justice. See
Commonwealth
v.
Freeman,
The petitioner claims that the admission of Arsenault’s initial guilty plea at their joint trial raises a confrontation problem. He urges that his right to confrontation was denied despite the fact that Arsenault took the witness stand and testified in detail concerning the events immediately preceding and following the fatal shooting of Lovinger. The confrontation claim rests on Arsen-ault’s professed inability to remember pleading guilty and that his memory failure prevented LeBlanc’s attorney from cross-examining him on the circumstances surrounding the plea. However, we need not decide this issue because we think the question central to the petitioner’s appeal is whether, as to LeBlanc, the erroneous admission of Arsenault’s constitutionally tainted guilty plea at their joint trial was harmless error beyond a reasonable doubt.
The evidence introduced at the 1955 trial revealed the following pertinent facts.
2
The three defendants, Ar-senault, Devlin and LeBlanc became acquainted while working at different times in a lunch room in Waltham. On October 23, 1954, Devlin and Arsenault visited a gun dealer in New Hampshire and Devlin purchased a .45
*175
calibre Colt automatic pistol stating that his name was Arthur Johnson. A week later Arsenault and Devlin returned to the same gun dealer and Arsenault purchased a .45 calibre Colt automatic under another assumed name. Thereafter, Devlin kept possession of the two guns at his home in Waltham. It appears that Arsenault left the Commonwealth for a few months. On or about February 1, 1955, Arsenault called Devlin by telephone and told him he was on his way home. “He arrived at Dev-lin’s home on the evening of February 3. On the following morning, Friday, February 4, Devlin and LeBlanc went to Watertown and bought two pairs of brown cotton gloves, a hat and a length of clothes line. They drove in LeBlanc’s automobile to Newton and LeBlanc pointed out a house at number 341 Waverley Avenue as the home of one Carl Silverman, a man who, he had told Devlin, was a wealthy dress manufacturer and was likely to be carrying a substantial amount of money on Fridays.”
Commonwealth
v.
Devlin,
The principal defence of all three defendants was that they had abandoned their criminal undertaking before the attempted armed robbery. Since the petitioner
*176
LeBlanc was the driver of the “getaway car” and was not present at the scene of the killing, his guilt rested on the Commonwealth’s proof that Arsenault shot and killed Merrill Lovinger while attempting a robbery in which the petitioner LeBlanc was also engaged, thereby making LeBlanc equally responsible for Arsenault’s acts. See
Commonwealth
v.
Devlin,
The Commonwealth could not convict LeBlanc of a felony murder if the gunman himself (Arsenault) had succeeded in proving abandonment of the contemplated robbery before the shooting. The admission at the trial of the three codefendants of Arsenault’s guilty plea to a charge of attempted armed robbery and murder was prejudicial to LeBlanc’s defence to the extent that it rested on Arsenault’s defence of abandonment.
However, there was overwhelming untainted evidence from Arsenault’s and Devlin’s own trial testimony and their statements to the police that would lead a jury to conclude beyond a reasonable doubt that there was no merit to Arsenault’s abandonment defence. In
Commonwealth
v.
Green,
Moreover, a careful reading of the trial transcript reveals that the petitioner’s chief defence was that, regard *178 less of whether Arsenault and Devlin had abandoned the criminal enterprise before the shooting, LeBlanc had abandoned the undertaking as soon as his codefendants had left his car. This defence was not prejudiced by the admission of Arsenault’s guilty plea because its success did not rest on Arsenault’s innocence but rather on LeBlanc’s credibility when he testified that he did not know of his codefendants’ scheme until they reached the scene of the robbery and that he abandoned the enterprise as soon as the others left his car. There was overwhelming untainted direct evidence from the codefendants’ statements to the police and from their trial testimony that LeBlanc was seriously involved in this criminal undertaking from its inception.
The remaining question is posed by LeBlanc’s claim that he abandoned the enterprise after his two codefend-ants left the car. In the circumstances, it is difficult to find fault with the jury’s apparent disbelief of this testimony. Moreover, it can hardly be argued with any degree of logic and common sense that LeBlanc’s credibility in this regard was prejudiced by the admission of Arsenault’s guilty plea. The codefendants’ plea of guilty could not possibly have been considered by the jury on the factual issue of whether LeBlanc had, in his own mind, decided to abandon the robbery attempt.
Our review of the record, including the voluminous trial transcript, leads us to conclude that “the properly admitted evidence of guilt is so overwhelming, and the prejudicial effect of the co-defendant’s [guilty plea] is so insignificant by comparison, that it is clear beyond a reasonable doubt that the improper . . . [admission of the guilty plea] was harmless error.”
Schneble
v.
Florida,
Judgment affirmed.
Notes
Arsenault received a new trial in 1970 in which he was again convicted of first degree murder. We affirmed this judgment in
Commonwealth
v.
Arsenault,
For a more complete and detailed summary of the evidence, see
Commonwealth
v.
Devlin,
LeBlanc testified that after dropping ofi: Arsenault and Devlin at the scene of the crime, he drove a few miles to a store to buy some gum and then drove to a gas station. After leaving the gas station, LeBlanc testified that he went back to Waverley Avenue out of curiosity to see what had happened.
In fact, there was evidence that Arsenault had not even abandoned his intent to rob
after
entering the house. Arsenault told the police that after entering the house, he told one of its occupants, “Stop your screaming, lady, I am not going to hurt you. All I want is money.”
Commonwealth
v.
Devlin,
It should be noted that the harmless error doctrine was not applicable in Arsenault’s appeal to the United States Supreme Court on grounds of denial of effective counsel when he pleaded guilty at his arraignment. The Supreme Court noted in both
Hamilton
v.
Alabama,
