They figured out how to immunize themselves during the Bush administration. Get a compliant lawyer to write a memo saying whatever you want to do is legal. Then you are relying on advice of counsel which tends to defeat the mens rea necessary to convict of a crime. The lawyer is also not liable because it's not a crime to give bad legal advice.

This technique is how everyone at the CIA got the hook for destroying video evidence of torture which had already been requested by a congressional committee and a federal court in 2005. It's also explains Yoo's farcical torture memos -- they may not pass the straight face test but they still were a major barrier to criminal liability for those who procured them.