It could be the smile, which Isiah Thomas flashes so disarmingly at all the right – and wrong – moments. It could be that Thomas is just as adept at sweet-talking David Stern as he seems to be with Knicks’ boss James Dolan.

Or it might be the guy just leads a charmed life.

There are not many other ways to explain why Thomas was courtside Monday night at Madison Square Garden, coaching his hapless Knicks as if the events of two nights earlier in the same building had never happened.

Give Stern some credit for trying to make sense of the Knicks-Nuggets brawl and dole out appropriate punishment. But on a day when he was acting tough by suspending everyone but the ushers in section 106, the best the commissioner could come up with when it came to Thomas was this: “You have to find something in order to suspend someone. Even in the NBA, there’s a presumption of innocence.”

Actually, there doesn’t have to be, because Stern is judge, jury and executioner in these kind of things. Don’t forget, this is a sports czar who tells his players what to wear and how to act and barely draws a peep in return.

So it was kind of odd to hear that the rules of this latest engagement were that you had to be caught on videotape throwing a punch at someone or wrestling with someone else in courtside seats to get punished.

Anything else is hearsay, not admittable in the court of the NBA.

That apparently includes both the chat Thomas had with Carmelo Anthony toward the end of the game, and the comments later which suggested retribution was indeed the order of the day.

And that’s why Thomas was coaching Monday night when common sense alone suggests he should have been watching the game on television somewhere far from Madison Square Garden.

“If I thought somebody gave a specific order to injure a player I would act quite differently,” Stern said. “I don’t think that happened here.”

Probably not, because Thomas was smiling when he told Anthony not to go into the paint in the game’s final minute and a half with the Nuggets comfortably ahead. He was either giving him a friendly reminder about player etiquette or inviting Anthony and his posse to dinner after the game.

If Stern was really looking for evidence, it didn’t take a lip reader to figure out what was going on. The Knicks were being embarrassed on a Saturday night at home, and they were drawing a line in the sand – come inside when the game is already won and we’ll take you down.

It doesn’t matter if Thomas specifically told Mardy Collins to grab J.R. Smith and wrestle him to the ground. The tone was already set by the coach, and his players knew what to do or risk losing their jobs.

Losing their coach for a few games wouldn’t have hurt the Knicks much, either. The team is filled with overpriced, underperforming players, most of them acquired by Thomas in his role as team president and general manager.

Stern likely had a few, well, stern words to say in private to Thomas about the whole mess. The best piece of advice, though, might be this:

Try doing a better job putting together and coaching your team.

Then you won’t have to worry about being embarrassed so often.