An illegal search and seizure violates your Fourth Amendment rights. To prevent that, the U.S. Constitution, as well as numerous laws, prohibit certain actions by the authorities. But how do you know if a search is illegal or not? When do the authorities have the right to search you without a warrant?

It depends. One of the most common ways the authorities will gain the right to conduct a search is just by asking permission. They count on the fact that most people, confronted by authority in a tense situation, will just give their consent. Doing that, however, could potentially lead to an arrest — and weaken your case in court, so it’s always best to refuse.

If the police believe that there is an emergency in your home, they will not need a warrant, either. For example, if they saw a suspect run into your yard and enter a back window, they may ask you to move aside to apprehend them. If somebody was screaming for help from inside your home, they could rightfully bust through the doors.

The police also don’t need to ask for your permission to take anything that is in plain view, and they won’t have to get a warrant to search you if they have arrested you. They can also search your person and sometimes your vehicle following an arrest.

There are times when a warrantless search by the authorities is considered valid — but it’s a good idea to talk to your attorney about the issue if your arrest on drug offenses or other criminal charges involved a search of your home or private property without a warrant.