NEW : Bulger 's attorneys say the federal government is covering up its role . NEW : The Justice Department declines to comment . Comment: Whitey Bulger faces 19 murder counts . A judge rules against part of his immunity claim .
NEW : Bulger 's attorneys say the federal government is covering up its role . NEW : The Justice Department declines to comment . Former mob boss Whitey Bulger faces 19 murder counts . A judge rules against part of his immunity claim .