Most of the probation terms and conditions state the probationer is not allowed access to weapons during the span of probation. It won't get op in trouble but it could lead to a probation violation for the probationer which could possibly result in revocation of probation and placement/incarceration. It's unlikely but to the strict ones and the persons behavior on probation and past record, still a possibility.
Checking the paperwork is definitely a great idea but how likely would roommate let op see the probation contact? That might just stir up drama and that's exactly what op doesn't need.