If they were searching for evidence of a crime, what crime was it?

They claimed they were looking for CSAM. There's a border search exception to the fourth amendment that says CBP can search your phone at the border. You aren't required to give them a password (but possibly a fingerprint or facial scan) but they can temporarily sieze it (and do god knows what to it).

The crime of disagreeing with the President.

The downvotes you get on this website for being completely correct never cease to astonish me.

I'd like some filter where if a comment is downvoted by IP addresses located in USA, they are considered as upvotes.

That isn't a crime in the US thanks to the first amendment.

> That isn't a crime in the US thanks to the first amendment.

Technically correct is not the same as practically correct.

Doesn't mean they won't still dump your phone and detain you as long as they can if they see a meme they don't like.

They can detain you for days if you're not white. (Kavanaugh Stop)