There was a similar occurrence at a border, this time an international airport, with a traveler returning from China. They axed him why he had been in China, and he declined to answer. They were a but shocked that someone would stand up to them. They detained him, bullied him, threatened him, and he calmly maintained he had the right to remain silent. He sat there, reading his book while they huddled and decided what to do with him. They apparently never had a traveler who stood up for his rights before.
Eventually, a supervisor confirmed for the others that his right to remain silent was, indeed, guaranteed even at border crossings. They inspected his bags and sent him on his way. He's lucky they didn't "find" some dope in his bags.
We're still at the stage in which the gummint pretends the constitution means something, so if their bullying doesn't make him yield, they eventually send him on his way.
