NEW YORK (AP) — The NFL Players Association filed a grievance with the league on Tuesday challenging its national anthem policy.

The union says that the new policy, which the league imposed without consultation with the NFLPA, is inconsistent with the collective bargaining agreement and infringes on players’ rights. The filing met a statute of limitations deadline and will be heard by an independent arbitrator, an NFLPA spokesman said.

In May, the NFL approved its national anthem policy at its owners meetings in Atlanta. The policy allows players to protest during the national anthem by staying in the locker room, but forbids them from sitting or taking a knee if they’re on the field or the sidelines.

Teams will be subject to fines if players don’t comply and will have the option of punishing players.

When the league announced the policy, Commissioner Roger Goodell called it a compromise aimed at putting the focus back on football after a tumultuous year in which television ratings dipped nearly 10 percent; some blamed the protests for such a drop. The union said at that time that it would file a grievance against any change in the collective bargaining agreement.