Law enforcement officials may request information about mobile phone devices by submitting a geofence warrant to an internet technology company. The tech company may provide officials with the tower data that logged mobile devices at a particular location. People may also refer to this as a reverse location search.
As reported by CNET, maps originally designed for sending advertisements have become a technique for law enforcement to identify possible suspects. Individuals with a mobile device using a location-tracking map may find themselves detained and questioned by police over an offense that they did not commit.
The U.S. Constitution prohibits unlawful searches
The Fourth Amendment of the U.S. Constitution prohibits officials from conducting unreasonable searches and seizures. Geofence search warrants, however, have come under scrutiny for possible violations of an individual’s Constitutional rights.
To obtain a search warrant, law enforcement generally needs to demonstrate probable cause that an individual carried out an offense. Requesting cellphone data on every individual in an exact location may not prove who engaged in wrongdoing, if at all.
Geofence evidence alone may not lead to a conviction
Cellphone data by itself may not always serve as strong enough evidence to charge an individual with an offense and obtain a conviction. As noted by NBC News, an initial request of a data batch may not serve to conclusively identify an individual.
Investigators must first cull through a batch of anonymous data and then seek a second search warrant to determine whether the owner of a mobile device has committed a crime. To obtain a conviction, a prosecutor must then prove to the court that the charged individual committed the alleged offense.