Pen Register - Pen Register Act

Pen Register Act

The Electronic Communications Privacy Act (ECPA) was passed in 1986 (Pub. L. No. 99-508, 100 Stat. 1848). There were three main provisions or Titles to the ECPA. Title III created the Pen Register Act, which included restrictions on private and law enforcement uses of pen registers. Private parties were generally restricted from using them unless they met one of the exceptions, which included an exception for the business providing the communication if it needed to do so to ensure the proper functioning of its business.

For law enforcement agencies to get a pen register approved for surveillance, they must get a court order from a judge. According to 18 U.S.C. § 3123(a)(1), the "court shall enter an ex parte order authorizing the installation and use of a pen register or trap and trace device anywhere within the United States, if the court finds that the attorney for the Government has certified to the court that the information likely to be obtained by such installation and use is relevant to an ongoing criminal investigation." Thus, a government attorney only needs to certify that information will 'likely' be obtained in relation to an 'ongoing criminal investigation'. This is the lowest requirement for receiving a court order under any of the ECPA's three titles. This is because in Smith v. Maryland, the Supreme Court ruled that use of a pen register does not constitute a search. The ruling held that only the content of a conversation should receive full constitutional protection under the right to privacy, since pen registers do not intercept conversation, they do not pose as much threat to this right.

Some have argued that the government should be required to present "specific and articulable facts" showing that the information to be gathered is relevant and material to an ongoing investigation. This is the standard used by Title II of the ECPA with regard to the contents of stored communications. And others believe probable cause should be required; Daniel Solove, Petricia Bellia, and Dierdre Mulligan say a warrant and probable cause should be necessary, and Paul Ohm argues that standard of proof should be replaced/reworked for electronic communications altogether.

The Pen Register Act did not include an exclusionary rule. While there were civil remedies for violations of the Act, evidence gained in violation of the Act can still be used against a defendant in court. There have also been calls for congress to add an exclusionary rule to the Pen Register Act, as this would make it more analogous to traditional Fourth Amendment protections. The penalty for violating the Pen Register Act is a misdemeanor, and it carries a prison sentence of not more than one year.