PFT finally addresses this obvious question :
"MANGINI: HERO OR HEEL?
Rich Cimini of the New York Daily News reports that the Patriots' efforts to videotape defensive signals was brought to light by former New England defensive coordinator Eric Mangini, who shared the information in 2006 with members of the Jets' organization.
"When Eric came, he said that's what they used to do," a source told Cimini. "Bill [Belichick] is going to be [ticked] at Eric. He kissed and told."
It would be easy to proclaim that Mangini did the right thing, ignoring the good-old-boys' network and bringing to light Belichick's dirty little secret.
But it would naive to do so, too.
Mangini didn't blow the whistle when he first learned of the situation, while Mangini was working for the Patriots. Instead, he took advantage of the competitive advantage, and parlayed it into a head-coaching job of his own.
And then Mangini blew the whistle in a manner that will eventually create for him a competitive advantage, since it will result in the imposition of some sort of a sanction on the Patriots.
But should Mangini be allowed to have it both ways? And did he bother to consider whether bringing this situation to light might indirectly call into question his own credentials to be a head coach?
Meanwhile, there's talk in league circles that Mangini will find it very hard to win the trust of anyone in the NFL moving forward. Even though Belichick has no cause to gripe about getting caught under circumstances where he knew that the opposing head coach knew what Belichick was doing, the truth is that anyone who chooses to confide in Mangini now or in the future will do so at his own peril.
Keep that in mind, Mike Tannenbaum, if/when you ever consider doing something like, say, contacting the agent for a player who is under contract with another team."