The Massachusetts Supreme Judicial Court (SJC) ruled yesterday to uphold the decision of a lower-court judge to grant a retrial in the high-profile case of Alexander Pring-Wilson, a former Harvard graduate student who was convicted in 2004 of fatally stabbing a Cambridge teenager.

Middlesex Superior Court Judge Regina L. Quinlan’s 2005 decision to reconsider previously inadmissible evidence, based on a post-trial SJC reinterpretation of the state’s self-defense law, was appealed by the prosecution this January.

The much-publicized Pring-Wilson saga began on the morning of Apr. 12, 2003 when he fatally stabbed 18-year-old Michael D. Colono five times in seventy seconds during an altercation outside a Western Avenue pizza parlor.

Although Pring-Wilson’s defense attorneys argued that his actions were in self-defense, the former Russian and Slavic Studies student was found guilty of voluntary manslaughter in October 2004 and sentenced to six to eight years in prison.

In the 2004 trial, Judge Quinlan barred defense lawyers from using evidence of Colono’s alleged history of violence, arguing that the contemporary self-defense law only permitted a victim’s violent history to be entered as evidence if the defendant had been aware of that history and thus had reasonable concern for his safety.

Pring-Wilson—who is currently under house arrest after being released on bail in 2004—did not know Colono or his cousin Samuel D. Rodriguez, who was also involved in the fight, prior to their altercation.

Quinlan was soon prompted to revisit her decision, when five months later the SJC allowed, in the case Commonwealth v. Adjutant, the admission of a victim’s violent history regardless of whether or not that history was known to the defendant.

In June 2005, Quinlan ruled to overturn Pring-Wilson’s conviction and move for a retrial.

While the prosecution appealed the decision this January, the SJC ruled in favor of Quinlan yesterday.

“As in Adjutant, in this case the identity of the first aggressor was essential, and the defendant sought aggressively and repeatedly to introduce evidence of Colono and Rodriguez’s violent histories to illuminate the matter,” wrote Chief Justice Margaret H. Marshall in the opinion.

E. Peter Parker, the defense attorney for Pring-Wilson, was pleased with the SJC’s verdict.

“The court held that at a retrial we get to go deeper into other violent conduct by not only Michael Colono, but also Samuel Rodriguez,” Parker said.

In a statement issued yesterday, Middlesex District Attorney Gerard T. Leone Jr. wrote that the facts of the case remain unchanged and the prosecution will not drop the charges against Pring-Wilson.

“We have reviewed the decision of the Supreme Judicial Court and fully intend to retry the defendant, Alexander Pring-Wilson, on behalf of the Commonwealth, the victim, and his family,” he wrote.

The date of the retrial has yet to be set.

—Staff writer Jamison A. Hill can be reached at jahill@fas.harvard.edu