A federal judge says she’ll decide Wednesday whether to block a prayer luncheon at the Air Force Academy after some faculty members and a religion watchdog group filed a lawsuit alleging it’s unconstitutional.

The lawsuit says academy commanders gave the impression they endorse the prayer luncheon, and that some faculty fear retribution if they don’t attend.

The academy says the event is voluntary. It denies commanders endorsed it.

U.S. District Judge Christine Arguello heard 3 ½ hours of arguments and testimony Tuesday. She refused to allow four faculty members to join the plaintiffs anonymously and questioned whether the remaining faculty member had legal standing to challenge the luncheon, which is scheduled for Thursday.

At least one witness is expected to testify Wednesday. Arguello says she’ll issue a ruling after that.