Congress Caught in Illegal Acts

How is it that those in Congress know that Insider Trading is Illegal but they have done it anyway. When it came to lite a Bill was passed saying they can't do it anymore. My problem with that is, That when they took Office they knew the Insider Trading was not only Wrong But Illegal. But Made the choice to ignore the Laws They Swore to Uphold. All those involved Should be Investigated and Prosecuted and made to Pay Back all they have Profited from their Illegal Ventures. And Never be allowed to hold another position within our Government.