text: Boy. There are a lot of people answering this question who really don't know the rules in this country. I speak from 11 years of law enforcement experience, many of those specifically developing traffic offenses into greater crimes. So people don't think I am feeding you a line of police BS, I included the laws that established each of the rights and reasons to search. Feel free to research them yourself so you can see I am giving you the straight scoop.\n\nThere are many times when the police can search your entire car, including your trunk, glove box, and even locked containers within your car, without a warrant. I'll lay out four of the most common techniques I use to search cars.\n\n(1) Consent. Can't go wrong here. If you ask for consent to search and the driver (or person in charge of the vehicle) gives you consent, you can search the entire vehicle. The consenting party has the authority to withdraw their consent and/or limit the areas you can search.\n\nOn reasons (2) through (4) consent makes no difference. If the police can meet one of these requirements, they will legally search your car with or without your consent.\n\n(2) Probable Cause. If you develop probable cause during a traffic stop, you may search the vehicle without a warrant. This is commonly called the "motor vehicle exception" to the search warrant rule. The authority for the police to do so was first established under a US supreme court case called Carroll v. United States. The courts have since expanded on this case and allowed the police to search items within the vehicle regardless of who claims ownership of the items. Under this technique, the police can only search areas where it is reasonable to believe the contraband they are searching for may be found. For example, if the police believe they are lookng for a rifle, they would not be able to search a purse. However, if they find the rifle and now believe they might be looking ammunition, the search of the purse is good.\n\n(3) Pursuant to arrest. If the police arrest you for a bookable offense while operating a motor vehicle, they may search the areas under your control (including the passenger compartment and possibly other areas of the car) for contraband or weapons that you may have discarded. This authority is established under case law named Chimel v. California.\n\n(4) Inventory search - If the police have the authority to tow your car, they may search it under the premise that they need to inventory all items contained within the car prior to towing the car. These searches were upheld under the community caretaking doctrine established under South Dakota v. Opperman.\n\nThere are other ways to get into a car. Too many to go into here. Truthfully, there is almost NEVER a time when the police need a warrant to search a car. In my 11 years, I think I have obtained a warrant for two or three of the probably 1000 cars I have searched, and those cars were firmly secured in the police impound lot pending the warrant.