Dajuan Marshall's convictions Monday for murder and gang participation — the first under a 2007 state law — could be thrown out because of juror misconduct, his lawyer said Tuesday.

Defense attorney Roland Walker plans to ask for a mistrial during a hearing Thursday in Baltimore Circuit Court. The proceeding was scheduled after a juror told the judge that at least one jury member had Googled Marshall's background during the trial. The woman also said members of the jury lost relatives to homicide, which was never properly disclosed during the selection process, according to Walker.

Jurors are not supposed to do outside research during a trial, so they can base their verdict solely on the evidence presented in court. They are supposed to alert the court to any conflicts of interest that might create bias, such as violence against a family member.

"None of this was revealed," Walker said.

Prosecutors declined to comment Tuesday, citing a Maryland rule that prohibits them from commenting on pending court matters.

Curious jurors have led to mistrials in Colorado, New Jersey and Florida, where nine admitted having done outside research during a federal drug trial. In Maryland, an appeals court overturned last year assault convictions in a case because a juror had used the Internet to look up a medical term used in court.

Marshall, a member of the Spyda Bloods gang, was convicted of killing rival Kenneth "Cash" Jones, who belonged to a different set of the local Bloods, known as the Pasadena Denver Lanes.

When Marshall was convicted, Gov. Martin O'Malley praised the decision, and Baltimore State's Attorney Patricia C. Jessamy called it a victory for the city's future. It was the first time that prosecutors had successfully argued a gang charge before a jury under the Maryland Gang Prosecution Act, a 2007 law that was criticized as too narrow. The statute was revised last year.

tricia.bishop@baltsun.com