3 states, including Texas, have pretty much completely done away with the right to organize mass protests ... and they didn't violate any civil rights.
Findlaw.com states that "Not every police search must be made under a lawfully executed warrant. The Supreme Court has ruled that warrantless police conduct may comply with the Fourth Amendment, so long as it's reasonable under the circumstances.
So, in what situations can police search your vehicle without a warrant? Here are some examples: