Football in Italy has enforced omerta so to speak on a Czech manager/coach Zdenek Zeman who blew the whistle on practices at all of the Italian clubs, especially the big clubs, and he hasn't gotten a gig at a decent Italian club since then.
The clubs and players justification was that they are expected to play 50 - 70 games a season (including League, Cup, European, and International matches for their respective country), so they need something to get them through the season.
Yeah he got banned back in 2004 for testing positive for cocaine while playing at Chelsea. That got him a 7 month ban (basically the rest of the season) as well as being sacked by his club.
Interestingly, Chelsea have tried to get compensation from Mutu with the figure quoted being £14.7 million! I think this is still being appealed. A lot of this refers to the transfer fee Chelsea paid for him in the first place
All the doping cases in football that I hear of seem to be in Italy. Borriello for some steroid, Maradona, Mutu, Davids for nandrolone, Jaap Stam (who suddenly decided to start taking nandrolone after leaving English football)..