Former Harvard University graduate student Alexander Pring-Wilson was convicted of voluntary manslaughter and sentenced to six to eight years in prison yesterday, closing a case that some said was a source of tension between Harvard and the Cambridge community.

Prosecutors charged Pring-Wilson with the April 2003 murder of Cambridge resident Michael Colono, who was 18 at the time of his death. Prosecutors argued that Pring-Wilson attacked Colono with a four-inch folding knife after Colono mocked Pring-Wilson for his drunken state one evening when Pring-Wilson stumbled home from a night out. Defense attorneys said Pring-Wilson acted in self-defense during the altercation with Colono, who had a criminal record.

Pring-Wilson, who had planned to obtain a master’s degree in Russian and Eurasian Studies, is the son of two Colorado Springs attorneys. Colono is a high-school dropout who fathered a child at 15.

But defense attorney Ann Kaufman said she thinks the prosecution unfairly portrayed Pring-Wilson as the product of an elite upbringing who believed his Harvard education put him above the law.

“[Pring-Wilson] worked all of his life,” Kaufman said during the sentencing hearing. “He comes from a family where all the children in the family worked. This isn’t about race, or class, or privilege or wealth.”

Judge Regina Quindlen sentenced Pring-Wilson the same day the jury concluded more than five days of deliberations. She could have sentenced Pring-Wilson to as much as 20 years behind bars.

Since the incident last year, local media reported the trial strained relations between Harvard and Cambridge.

But Cambridge Mayor Michael Sullivan said he thinks many people exaggerated the impact of the trial on Harvard-Cambridge relations. He said issues between the university and the city have “ebbed and flowed” over many generations since Harvard began building in the community in the late 1920s.

“I think many people tried to paint this as a town-gown offense,” Sullivan said. “I think Mr. Pring-Wilson committed the offense in his own right.”

Harvard Kennedy School of Government Professor William Agpar said he thinks Harvard has a good relationship with the community and never expected occasional tensions to adversely affect the judicial system. He said he is confident local juries would never engage in bias for or against Harvard.

“Public safety is important to everyone, including students who live in Cambridge,” said Agpar, who is also a senior scholar at Harvard’s Joint Center for Housing Studies. “From time to time there are tensions, but I don’t think they’d rise to the level where they affect juries.”

Harvard Faculty of Arts and Sciences spokesman Steve Bradt declined to comment on the verdict and said he did not anticipate Harvard taking a position on the matter.

— The Associated Press contributed to this report.