I think most of them are clean.
The NBA is pretty dirty though. Not every game....but I've got eyes. There are even names for what happens.
1- "Star treatment". Everyone involved with the game knows about that. Somehow giving a player an advantage over other players isn't called "fixing games"....but it absolutely
is. Any player who tried to get within 5 feet of Michael Jordan in the 90s in a close game knows all about that. Good luck beating a team with a great player
and protection from the refs no matter how well you play that day.
2-"Home cooking". Is there any reason why a home team should get favorable calls? Nope. That's fixing games too.
3-"Playoff basketball". Is there a reason why the rules should be different once the playoffs start? Nope. But somehow, once the regular season ends, the same action is suddenly just "hard defense" instead of a "foul". Too bad for your team if it doesn't have some bruisers on the squad. Skills suddenly are secondary to a test of manhood.
4-Lakers/Kings '02 and Mavs/Heat '06. That's the most blatant fixing of series I've ever seen. The world noticed too. Ralph Nader even tried to have the NBA investigated after the Lakers/Kings series. And in '06, there was no way Stern was going to hand Mark Cuban that trophy. Dwayne Wade suddenly found out how easy the game is when you are treated like Michael Jordan by the refs.
The funny thing about the NBA is how fans used to say, "If it was fixed, a player, ref, coach, or owner would bust them! One of them would eventually have something to gain!" ....So what happens when a player, coach, or owner speaks up? They are fined and mocked. What happened when a ref spoke up? ....Well...the story then changed to "You can't trust him! He's got a book to sell!" So obviously nothing will convince some fans. But even Phil Jackson confirmed what happened in the '06 Finals:
http://sports.espn.go.com/dallas/nba/news/story?id=6211182&campaign=rss&source=NBAHeadlines
Ironically, Phil was talking about how Cuban learned to keep his mouth shut by being punished in the '06 Finals. I noticed the Mavs were able to play some pretty hard defense on the Lakers during their series last week. They weren't allowed in the same zip code as Wade in '06. Maybe Phil just got the same treatment Cuban got in '06?