In the Mapp v. Ohio ruling on June 19, 1961, the Supreme Court used the due process clause of the Fourteenth Amendment to expand the scope of the Fourth Amendment, which forbade searches and seizures of property without a warrant. The Court had ruled in the 1914 case Weeks v. United States that evidence illicitly collected by law enforcement officers could not be used in federal courts. Known in legal terms as the exclusionary rule, this legal protection was designed to ensure that police officers complied with the Fourth Amendment.