If the data gathered went beyond the scope of a warrant that was issued, the use of that data may constitute a trespass and may have impeded on a defendant’s reasonable expectation of privacy. In United States v. Jones, law enforcement put a GPS device in the defendant’s vehicle and monitored his movement for a month. The GPS device was not installed within the timeframe specified by the warrant, nor was the device installed within the location specified by the warrant. The warrant was found to be invalid and, in the majority opinion, Justice Scalia indicated that the warrantless search was a violation of Jones’ Fourth Amendment right, constituting a trespass. In his concurring opinion, Justice Alito also brought up a reasonable expectation of privacy argument that the use of longer-term GPS monitoring in investigations of most offenses, beyond four weeks, impinges on one’s expectations of privacy.