Watching the Patriots-Broncos game (go Broncos!), the commentators were talking about some player who has had a lot of fines over the years. I can’t remember who the play-by-play guy is, but he asked if fines are tax-deductible and Madden jumped right in and said that yes, they are.
So I figure I better ask the Dopers what the truth is, since this was a comment by Madden we’re talking about.
WAGing here - I suppose fines could be considered a business loss, or perhaps a professional fee. I can deduct what the state charges me every year for my professional license, but they’ve never fined me.
My guess is that are aren’t so much tax deductable as they just don’t show up on your pay stub.
You have the case of an NFL kind of guy making $960,000 a year, or $80,000 a month. He gets fined $10,000. Next month he gets $70,000 on his check, (less all the taxes and stuff). Comes time for the W-4s to come out and he has made $950,000 for the year.
But, since Madden coached in the NFL for several years no doubt this conversation came up often in the locker room.
Well, a lot depends on HOW the fines are collected. I’ve read (I can’t vouch for the accuracy of this charge) that, in many instances, the “fines” are given to one charity or another- sometimes directly, sometimes indirectly.
So, in at least some cases, players are, in effect, making a mandatory contribution to, say the United Way, and then claiming the “donation” as a tax deduction.
If a cab driver gets fined for a traffic violation while on duty, is it tax-deductible? It’s a loss related to his job, but it comes from doing some part of his job badly, which seems to also be the case for a fined athlete.
That said, I have no actual information to contribute. 
If a cab driver is fined for speeding or whatever, then those fines are not deductible (at least not in this part of the world: the USA may be different.) It’s just a matter of public policy.
The situation with sports players is different; they are being fined by their employer so, (and I’m guessing) I would say the fines are deductible.