A made guy who turns rat is probably going to be hunted because he's a bigger danger than a cop. An undercover cop finally surfaces, the mob guys are busted, there's a trial, end of story. But a family is far more likely to take action against a made member who turns because he's an ongoing danger--not only to family members but to other mobsters with whom he's been in contact. The usual deal the government cuts with mob turncoats is that they have to testify anytime the government wants them to--meaning years and years. And the rats are likely to say anything the government wants in order to get a conviction. You've probably read recently that Thomas (Huck) Carbonaro, who had been a member of Gravano's crew, was dispatched by the Gambinos to whack Sammy Da Bull. He came close. Part of their motive was to prove to other families that they could "take care of their problems."