Courthouse security officials say more than 30 people were involved in the fight Wednesday morning.
Four people were arrested. There were no significant injuries in the brawl.
The fight involved family and friends of the defendant, Charles Trotter, and of the shooting victims, 26-year-olds Dexter Joseph and Marcel Lovejoy. Trotter is accused of fatally shooting Joseph and Lovejoy on Jan. 3, 2015.
The judge said he hopes isolating the jury will prevent the incident from affecting the jurors’ ability to hear the case fairly.
Security has been increased on the floor.