Per NFL Media's Albert Breer, the NFL Players Association is looking into a possible violation of the collective bargaining agreement, specifically the portion which says club officials cannot tell a player that offseason activities are not voluntary.
Patriots coach Bill Belichick had no comment Thursday when asked about the reports on Butler's discipline.
The situation seems like an awkward one for the player who made the defining play of Super Bowl XLIX. By all accounts, he's not complaining about anything that might have happened.
"I really don't have a comment about that," he said. "I'm just glad to get back here, participating, just getting better. Trying to get better. That's all."
True to Patriot Form, Butler is staying quiet while New England wraps up their final OTA workouts of the season ahead of next week's mandatory minicamp.
In the meantime, Butler told reporters that he's watching film and talking to teammates about what he missed. Like Bill Belichick, he's probably hoping this all blows over soon.