[Zak]

> That anything within 100 miles of the border is constitution free tosses that out

That's a misconception. Border/immigration agents can operate inside this zone, including making stops with reasonable suspicion or running checkpoints where everyone is stopped with no suspicion. The checkpoints are limited in scope, and do not provide authority for searching electronic devices. Some people, including a couple dissenting supreme court justices do feel the checkpoint part violates the constitution.

That's distinct from the border search exemption, which allows inspection of everyone and everything crossing the border. It only exists when someone is actually crossing the border and does not allow CBP to stop or search people who are not crossing the border.

Edit: https://www.aclu.org/know-your-rights/border-zone