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.