But one bad apple really can spoil the bunch — or taint it by association.

This isn’t about reality anymore. It’s about perception. And none of Stern’s evident agony can change that.

Donaghy worked 139 regular-season games over the past two years, eight playoff games and four pre-season games. According to Stern, he was betting games during that time, most likely games he was working.

The commissioner could say that the issue of point-shaving or game-fixing hasn’t been determined, but you’d have to be incredibly naïve to believe that Donaghy could work games that he had money on and not have that influence how often he blew his whistle and who his calls were for and against.

The NBA, Stern said, has 30 observers — one for each team — who watch every game and rate the performance of the officials. There are already several cases that have been unearthed about strange things happening on Donaghy’s watch — a basket wasn’t recorded in a Toronto-Atlanta game, with the result being a wrong score that didn’t affect who won the game but changed who won the bets. In a Knicks game, he sent New York to the line 39 times. In a Toronto-76ers game he worked, so much cash came down on the Raptors just before the game, it changed the betting line.

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How can it be that no one noticed any of this? That’s the question I can’t make go away, and neither can David Stern, no matter how much personal integrity he has and how many security forces he has at his disposal.

Stern said the league will continue to improve the way it monitors its officials, whom he called "the best in the world." But the nature of basketball is such that huge numbers of calls come down to a referee’s judgment.

As long as that’s the case, there’s no system Stern can conceive of, no number of press conferences he can hold, that can set fans’ minds at ease.

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