In 2012, in terms of Criminal Defense and the GPS, the United States Supreme Court ruled in US v. Antoine Jones, that government installation of a GPS device on a criminal defendant’s vehicle, and its use of that device to monitor the vehicle’s movements, is considered a search under the 4th Amendment. Therefore, in order for police to track a vehicle using a GPS device, a search warrant must be obtained by the police prior to installation.  assault crimes Such installation without a warrant, is considered to be a trespass. Other courts have ruled along this line as well. The Supreme Court found that using drug-sniffing dogs around a suspect’s front porch without a warrant or consent was also an unreasonable search as police were trespassing. This suggests that once the police secure a search warrant, they can attach a tracker on the outside of the car (or underneath it), as opposed to entering into the vehicle to install which might require a warrant authorizing the search of the vehicle. Now there are some exceptions to this rule which include: 1) Consent; 2) Federal agents (not state or local officials) may install tracking devices on vehicles entering the US from a foreign country and can monitor vehicles for 48 hours without a search warrant or reasonable suspicion.

Pennsylvania courts, have dealt with Criminal Defense and Gps, have had occasion to apply the ruling in Jonesignorance or mistake as a defense In Commonwealth v. Arthur, a panel of the Superior Court reversed a Montgomery County trial court ruling that suppressed evidence seized as a result of a tracking device. In that case, the Court ruled that the Defendant had no expectation of privacy because he did not possess an ownership interest in the car tracked. It’s pretty clear that under Jones, and Pennsylvania court’s application of that ruling, police are required to obtain a warrant in order to track a target using GPS. Once having that warrant, whether they can attach the tracker on a car while on private property is, I believe, an unsettled question, although the Jones court did cite the fact that the government “physically occupied private property for the purpose of obtaining (evidence)…” in that case. It’s certainly more problematic for police to attach a tracker on the inside of the vehicle than the outside, while the vehicle is on private property as opposed to parked in a public lot. The notion of whether a device or the battery that powers it can be replaced without an additional warrant or court order may be a matter decided by the parameters of the initial warrant itself.