PORTLAND, Maine — The Maine Supreme Judicial Court on Tuesday unanimously upheld the conviction and sentence of a Bangor man found guilty of murder.

Zachary Carr , 21, is serving a 35-year sentence for the shooting death of John “Bobby” Surles, 19, of Bangor in a Jan. 27, 2010, street fight between two rival groups.

Carr was found guilty of murder and not guilty of manslaughter by a Penobscot County jury in March 2011. After Carr’s sentencing, Maine Assistant Attorney General Andrew Benson, who prosecuted the case, confirmed that before the trial, Carr turned down an offer to plead guilty to manslaughter and serve less than 10 years in prison.

Justices heard oral arguments in the case last month when they convened at the Penobscot Judicial Center in Bangor.

Bangor attorney Hunter Tzovarras, who did not represent Carr at his trial, had sought a new trial for Carr because a recording of an interview with Jason Blake, a key witness, was not turned over to the defense team until after the weeklong trial.

The justices disagreed.

“We are persuaded that Carr did receive a fair trial in this matter,” Justice Ellen Gorman wrote in a nine-page opinion for the court. “The court’s findings — that the withholding of the recording was an unintentional error; that the prosecutor made ‘more than diligent’ efforts to obtain and disclose all discoverable materials; that the interview summary that was provided to Carr well before trial contained no significant discrepancies from the recording itself; that, due to the timing of the discovery of the recording, the state also did not have the benefit of that evidence in its trial preparation; that the eyewitness’s testimony at trial was more beneficial to Carr than the recording would have been; and that, because the eyewitness refused to speak with the state before trial, but did speak with Carr’s counsel before trial, Carr was not unfairly surprised by the eyewitness’s testimony, and was in fact ‘somewhat more prepared’ for the eyewitness’s testimony than the state — are amply supported by the record, and justify the court’s conclusion that Carr was not entitled to a new trial.”

Tzovarras also unsuccessfully argued that the evidence was insufficient to sustain Carr’s murder conviction and to disprove his claims of self-defense.

“We discern no error in the court’s entry of the judgment of conviction or its sentencing analysis. There was ample evidence presented at trial on which a reasonable jury could find, beyond a reasonable doubt, both that the state disproved Carr’s assertion that he acted in self-defense, and that Carr committed each element of intentional and knowing murder,” Gorman concluded for the court.

Tzovarras said Tuesday that he and Carr were disappointed in the justices’ decision.

“The trial was essentially one of credibility and [Carr’s] trial lawyers not having Jason Blake’s recorded interview during the preparation phase or trial could have made the difference in a close case,” Tzovarras said in an email. “At the very least, it seems to taint the whole process when the defense doesn’t get a recorded statement from an eyewitness until after the trial is over.”

Assistant Attorney General Donald Macomber, who handled the appeal, said his office was pleased with the court’s decision.

“The justices had little difficulty upholding Mr. Carr’s murder conviction and lengthy sentence,” the prosecutor said in an email. “This should send a signal not just to the Bangor community but to the entire state that guns have no place in a fistfight. While no court decision can bring Mr. Surles back to life, we hope that the result will bring some small measure of comfort to his family.”