I'm not in the lawyerin bizness but I think that ya'll are correct about that leaning toward RICO. If so, it could be something like blackmail/bribery, laundering money, or obstruction of justice. Obstruction of justice can also be blackmail and bribery, but toss in murder, threatening to burn your granny's house down if you don't do something your told to, etc...only it's against witnesses, LE, people working in positions of the law, etc...
It also looks like there's a pretty stiff penalty for convictions under this statue, so it could have also been a way to add extra pressure to get people to talk, to cooperate with LE. Not sure.