The Supreme Court on Thursday ruled against a Boston man seeking to overturn his murder conviction because his lawyer failed to object when the trial judge closed the courtroom during jury selection.

Justice Anthony Kennedy said in the 7-2 ruling that the error Kentel Weaver's lawyer committed did not appear to affect the outcome of the case. Weaver was found guilty in the 2003 murder of a 15-year-old boy.

The lawyer's failure to object prevented Weaver's mother and others from watching what should have been a public jury selection process. The judge had closed the courtroom because it was overcrowded.

Weaver's lawyer later testified that he mistakenly believed closing the court for jury selection was permitted. In fact, it violates the Sixth Amendment right to a public trial.

But Kennedy said Weaver did not show a "reasonable probability of a different outcome but for counsel's failure to object." He said the lawyer's shortcomings did not lead to a "fundamentally unfair trial."

Weaver was only 16 years old at the time of murder. Prosecutors said the victim, Germaine Rucker, was attacked by a group of men and boys after selling some jewelry to a woman, and was shot twice.

Witnesses saw a boy wearing a baseball cap pull a pistol from his pants leg. The cap fell off and was recovered by police, who discovered Weaver's DNA on it. Weaver confessed to his mother, and later, to police when his mother brought him to the police station.

Before trial, the judge ordered the courtroom closed because it was overcrowded with 90 prospective jurors, forcing some to stand in the hallway. Weaver's mother and a friend tried to get in but were refused entry.