If you suddenly clam up when they get to a specific question, they're probably going to be able to guess the answer.

In the US, that doesn't mean anything legally speaking. They might know then that this means you have a lot of cash on you, but that's not probably cause for a search. They still have to get permission or a warrant to search.

I don’t know about probable cause for a search, but legally speaking, clamming up to a specific question, as opposed to explicitly invoking the 5th amendment right, currently means something in trial, as ruled in Salinas v. Texas.

https://www.oyez.org/cases/2012/12-246

I don’t see how telling the officer you have $87k is probable cause for a search, anyway.

Isn't it a probable cause to search your car, since it's the car and the cash that has broken the law, and has no rights to privacy?

No.

First, it is not illegal to have a car or cash.

Second, in the US at least the government does recognize a limited right to privacy in the form of the 4th amendment which spies to States as well. An officer cannot search you, your car or your home without a warrant from a judge or a tangible reason to believe you are committing a crime.

Or if you agree to a search!

That's why the statement at the top of this thread is

> The lesson here is clear: do not cooperate with the police

Suddenly clamming up is a problem, doing so less suddenly is not (I'm elsewhere in this thread roughly advocating for clamming up about anything not directly related to the traffic stop)

Clamming up when a patrol officer goes off script means nothing more than you know that he knows that you know he's off script.