"These technologies convert traditional 'tailing' of a suspect into a new and different type of surveillance, paired with new and powerful digital analytics tools, that alters our analysis of expectations of privacy in a public place," the report said.

The report highlights a case that the later this year involving the government's authority to conduct prolonged GPS tracking of suspects in criminal cases without first obtaining a court warrant.

The case involves the FBI's use of a GPS tracking device to continuously monitor the movements of Antoine Jones, a suspect in a drug investigation, for four weeks. The device, which was used without a court warrant, provided information that was later used to convict Jones.

Jones argued that the evidence gathered against him should be thrown out because it was gathered via warrantless tracking, which he contends violated his Fourth Amendment rights.

Prosecutors have argued that the GPS device was used in accordance with precedent established in earlier cases involving warrantless GPS tracking.