Robel Phillipos

BOSTON — The trial of a third friend of Boston Marathon bombing suspect Dzhokhar Tsarnaev ended in another conviction, but the amount of time the jury spent deliberating and its somewhat mixed verdict could help federal prosecutors argue against any new defense bid to move Tsarnaev’s trial outside of Boston, according to some legal observers.

Robel Phillipos, 21, of Cambridge was convicted Tuesday of lying to the FBI during the bombing investigation, specifically about being present in Tsarnaev’s dorm room when two other friends removed a backpack containing fireworks and other potentially incriminating evidence.

The jury deliberated for more than 35 hours over six days before finding Phillipos not guilty of telling four of the nine lies he was accused of by prosecutors. His lawyers had argued that Phillipos was intimidated when he was questioned by the FBI and that he had smoked so much marijuana that his memory was clouded.

“Any time a jury splits the verdict, it shows deliberation and contemplation,” said Gerry Leone, a former state and federal prosecutor in Massachusetts. “It sort of weighs against this whole idea that you can’t get impartial and unbiased juries on these terrorism-related or marathon-related cases.”

Tsarnaev’s lawyers had argued the trial should be moved outside Boston — preferably to Washington, D.C. — citing the broad emotional impact the bombing had on Massachusetts residents and the intense media coverage in the state. But Judge George O’Toole Jr. rejected that request, saying there’s no reason to assume in advance a fair jury cannot be selected in Boston.

Mark Pearlstein, a former federal prosecutor in Boston who is now a defense lawyer, said if Tsarnaev’s lawyers raise the change of venue issue again, prosecutors could cite the jury’s thoughtful deliberations in the Phillipos case as evidence residents of Massachusetts “are not so overwhelmed by the tragic context of the marathon bombings and are actually able to sift through the evidence very carefully.”

“All of that is support for the notion that Tsarnaev can get a fair trial here, but Tsarnaev’s lawyers obviously would say there is a big difference between pot-smoking college students who told some lies and somebody who is accused of having killed innocent people on Marathon Monday,” Pearlstein said.