They can still hold you for a long time (days?) at the border without being formally charged with anything. That's what I've been told, not sure how true it is.

They can still hold you for a long time (days?) at the border without being formally charged with anything. That's what I've been told, not sure how true it is. A Canadian entering the U.S was held for 2 weeks with no charges - not just a entry denial.