Watching this video got me thinking. I live in Las Vegas and travel in the southwest a lot. In order to cross Hover Damn into Arizona, you must pass through a security checkpoint where they search ALL RVs, trucks, trailers ect. before allowing them to pass. However, they do not search cars in most cases.
How is it they circumvent the 4th amendment with these searches? I mean, you can refuse to consent, but if you do refuse they don't let you pass the checkpoint. Is there something special in the law that allows them the power of warrantless search, because they search every RV/truck/trailer (sort of like a DUI checkpoint), since they are searching every vehicle of a certain type, somehow that makes the search legal?
And, if that does make the search legal, doesn't that also make the question the border agents asked in this video legal as well, since I assume they are asking that same question to everyone?