I believe you can refuse to comply with those checkpoints.
I know that people have done so, and the result has been somewhat interesting. Based on what I've read, I suspect that the actual protection from the 5th amendment is currently being interpreted much more narrowly than they were historically, and if the agents pushed it you have a lot less immunity from having to answer their questions than you would like.
Please note that I said, "I suspect". I have read conflicting opinions on this in the past, have no idea which is right, and so it is necessary to put significant disclaimers next to anything that I say on the topic.
Comments
I believe you can refuse to comply with those checkpoints.
I know that people have done so, and the result has been somewhat interesting. Based on what I've read, I suspect that the actual protection from the 5th amendment is currently being interpreted much more narrowly than they were historically, and if the agents pushed it you have a lot less immunity from having to answer their questions than you would like.
Please note that I said, "I suspect". I have read conflicting opinions on this in the past, have no idea which is right, and so it is necessary to put significant disclaimers next to anything that I say on the topic.