Pen/Trap orders are among the most frequently employed criminal law en-forcement mechanisms.140 The use of pen registers,141 or trap and trace de-vices,142 is governed by the “Pen/Trap Statute.”143 This statute grants the gov-ernment access to information related to the processing and transmission of wire or electronic communications, but not the contents of those communica-tions.144 The government has argued in a number of cases that this includes location information for calls made from cell phones.

The government’s advantage from obtaining tracking location information via the Pen/Trap Statute, as opposed to other portions of the ECPA, is the stat-ute’s relatively low standard of proof.146 An order authorizing the use of a pen/trap device requires only that the government show that “the information likely to be obtained by such installation and use is relevant to an ongoing criminal investigation.”147 Such little protection stems from the Supreme Court’s holding in Smith v. Maryland that no reasonable expectation of privacy exists as to the phone numbers a person dials.148 Compared to the SCA’s spe-cific and articulable facts standard or a probable cause requirement, this stan-dard is relatively low and easier for the government to meet.149 Thus, this lower threshold, if accepted by the courts, would permit access to invaluable infor-mation while severely encroaching on Fourth Amendment protections.

The Communications Assistance to Law Enforcement Act (“CALEA”),150 however, makes clear why the ECPA’s Pen/Trap Statute is not applicable to GPS phones. CALEA was enacted in 1994 “to preserve the government’s abil-ity, pursuant to court order or other lawful authorization, to intercept commu-nications involving advanced technologies such as digital or wireless transmis-sion modes.”151 It provides that a communications carrier may not provide, and the government may not obtain, “any information that may disclose the physi-cal location of the subscriber” when the government’s access is “acquired solely pursuant to the authority for pen registers and trap and trace devices.”152 Nonetheless, the government has attempted to argue the Pen/Trap Statute as a basis for obtaining such information