Clark County District Judge Jackie Glass sentenced Simpson in December 2008 to nine to 33 years in prison on charges including first-degree kidnapping and robbery and assault with a deadly weapon.
During a hearing in May, Simpson's current lawyers, Pamela Palm and Ozzie Fumo, presented evidence and questioned witnesses including trial lawyer Yale Galanter about whether he knew in advance about the September 2007 plan for Simpson and several other men to confront to memorabilia deals in a Las Vegas hotel room.
Simpson argues that he was trying to retrieve items stolen from him after his 1995 "trial of the century" acquittal in Los Angeles.
Bell hasn't indicated when she plans to issue her decision, but told a KSNV-TV interviewer for a segment aired this week in Las Vegas that she still had "some writing to do."
Associated Press writer Ken Ritter in Las Vegas contributed to this report.