When the police pull you over, you may be fearful due to all of the media coverage about harmful interactions with police. You know you should cooperate to stay safe, but you also want to protect your rights.
It is helpful to know when the police can legally stop you and what they can do next. If they do not follow protocol, any charges arising from the incident could be dismissed.
Probable cause
The general idea behind probable cause is to prevent unreasonable searches and seizures, a right protected by the Fourth Amendment of the Constitution. Probable cause means that a police officer must "have adequate reason to arrest someone, conduct a search, or seize property relating to an alleged crime". The law regarding probable cause can be complex depending on circumstances.
Reasonable suspicion and traffic stops
Most often, the police will stop you while you are driving. To do so, they must have reasonable suspicion that a person has done something wrong. Reasonable suspicion is "objectively justifiable suspicion that is based on specific facts or circumstances and that justifies stopping someone".
Examples of reasonable suspicion for traffic stops include:
- Driving without a license plate or with an expired registration sticker
- Going over the speed limit
- Not following traffic laws
- Doing something else illegal while driving, such as drinking
Furthermore, if someone has reported you or another driver with a similar vehicle, the police may pull you over to investigate. Whatever the reason, you do not have to consent to a search.
Anything illicit in plain sight can provide probable cause, though, allowing for a legal search. However, if the original traffic stop was unnecessary, the court cannot accept evidence from the search. One exception is if the police discover there is a warrant for your arrest. Then whatever they find is permissible in court.
Other types of stops
Traffic stops are the most common, but law enforcement officials may also stop you on the street or inside a public place. The same rules apply: The police must have reasonable suspicion to stop you (such as breaking a traffic rule or looking like you have a concealed weapon) and probable cause to arrest or search you.