NY state is the equivalent of the former East Germany, without the Stasi. Its a one party state, actually run by the bureaucracy, that is steadily in decline, when eventually its one-horse economy (Wall Street) will collapse. Even many Republicans are basically Democrats, or accept their perpetual minority status because they gain too.
Maybe Coumo thought that the commission would only go after small fry. Then he could claim that he was cleaning up his own party.