Actually, if you are a member of Congress, none of this applies. Under Article 1 Section 6 of the US Constitution, the police cannot arrest or even question a Member of Congress if he is on his way to or from a debate in Congress.
The Police did the right thing in Patches' case, as uncomfortable as that fact is. Patches has a special immunity. Yet one more reason to never send a Kennedy to Congress.
You have a point there. The only problem: there was no debate going on at 3am.
I know there is the law as you wrote, but I also think the law can be an ass sometimes too, as Shakesphere wrote. (pardon the paraphrasing, but I'm trying to make a valid point here) :0 )