[sunmars]

That was the main thing, police can check if you are illegal before releasing you.

[Ramius]

That was the main thing, police can check if you are illegal before releasing you. That's what it sounds like to me. That's the most important part. If they need a warrant to then make an arrest... well, OK. That's do-able. It's a hassle, but it sounds like the police get to keep the ability to check up on immigration status.