Colin Campbell has learned a lesson - and the hockey world has also learned something about Colin Campbell.
Campbell, the NHL vice-president in charge of discipline, is in hot water over e-mails he sent between three and five years ago.
In them, he berates referees, calls one player "a little fake artist" and displays such a special interest in some games involving his son (Gregory Campbell, the Boston Bruins forward) that some people are alleging a conflict of interest and demanding his dismissal.
The NHL office immediately sided with Campbell, praising his years of service to the game.
By all accounts, Campbell is a man of integrity, a hockey man through and through, and someone who places the interests of the game first and foremost.
However, this case is very damaging, and it is Campbell's credibility that has been damaged. Already burdened with a thankless job - handing out fines and suspensions - Campbell's decisions will be questioned and debated more than ever.
Worse still is the perception - true or not - that Campbell's judgment might not be impartial in all cases.
Campbell comes from a blue-collar background; he was a farmer before he was an NHL player. He is a straight-shooter who is not above using colourful language to make his points. A good man, a great hockey mind and a boon to the game. But after 12 years as the NHL's bad cop, maybe it is time to try a new job.