The U.S. Supreme Court has effectively held that the police can’t search a rental car simply on the basis that someone driving it isn’t listed on the rental agreement. The Court established that someone who has permission to use a car from the person who rented the car doesn’t lose all Fourth Amendment rights merely by not being on the rental agreement. (Byrd v. U.S., 584 U. S. ____ (2018).)
For more on the case, and on rules on this general topic, read up on car searches after traffic stops.
Effective date: May 14, 2018