You mean, "it smells like weed"?
https://en.wikipedia.org/wiki/United_States_Border_Patrol_in...
> The United States Supreme Court ruled that Border Patrol agents may stop a vehicle at fixed checkpoints for brief questioning of its occupants even if there is no reason to believe that the particular vehicle contains illegal people. The Court further held that Border Patrol agents "have wide discretion" to refer motorists selectively to a secondary inspection area for additional brief questioning.
There's no outward sign of citizenship, nor are citizens required to carry proof of it.
I take issue with the bad faith interpretation by the ACLU that has so misinformed the public. It undermines their mission.
"Odd because I have been detained at CBP checkpoints inside the US"
You cannot stop a person inside the US and request they produce any kind of identification without first detaining them. The CBP detains everyone. If you prove you're a citizen, you can leave after being detained.
This is different than everywhere else in the country. It is the fundamental civil rights violation which is being objected to above.
How does that even work? I don't know anyone who regularly carries around their passport, or some other proof of citizenship. A driver's license or state ID isn't enough to establish citizenship, or even legal immigration status. (Though I suppose they could cross-reference your identity, based on the state-issued ID, with whatever databases have that information.)
Personally I refused to answer, set the parking brake, turned the car off, and removed the key. They told me to go to secondary and I just didn't say anything and kept looking forward. Eventually enough traffic backed up behind me on the freeway they just waived me through to get traffic moving again. I know the courts have found it to be legal, but I don't care. I'm not going to comply. If no one complied they wouldn't be able to get away with this shit. Unfortunately most people don't care.
Usually with the border patrol stops a vehicle they ask if there are any non-citizens in the vehicle. If you lie at this point and they don't believe you it would likely give cause to investigate further. So either tell the truth or shut up.
Given that any documented not-citizens are supposed to carry their permanent resident card or passport with them at all times then the assumption is that any not-citizens are doing just that so can easily prove their status. Not everyone does and in recent years they've been policing this a lot harder than they used to and you can find yourself in hot water if you encounter the wrong officer (most cases you will get a very stern talking to).
So if you aren't carrying a permanent resident card or passport then the assumption is that you are either a citizen or undocumented. How hard they push to find out which depends on the bias of the officer making the stop.
Look up "stop and identify." You don't have to present any kind of documents if you're a citizen. You do have to identify yourself, and yes it's vaguely defined. Generally this means name and address. An ID will also provide this info.
The officers will call in your information, check warrants and resident status, etc.