United States v. Duggan

Under the Foreign Intelligence Surveillance Act (FISA), the federal government applied for and obtained permission to conduct electronic surveillance on Gabriel Megahey (defendant), an Irish national who was seeking political asylum in the United States. Megahey was the self-proclaimed leader of the Provisional Irish Republican Army (PIRA), a terrorist group based in Northern Ireland. Through its surveillance, the government discovered that Megahey, his American assistant Andrew Duggan (defendant), and two other PIRA operatives who were illegally present in the United States (defendants) were part of a larger network of men who were involved in secretly acquiring explosives, weapons, and other equipment to be exported to Northern Ireland for use in terrorist activities. The government charged the four men with various federal crimes related to unlawful transportation of weapons. At trial, the government’s evidence included videotapes of meetings, audiotapes of telephone conversations, and the testimony of federal agents regarding PIRA’s operations and the men’s activities in the United States. The court overruled the men’s objections to the use of the FISA materials against them. A jury returned convictions on nearly all charges, and the men appealed. The men primarily challenged the constitutionality of FISA, arguing that electronic surveillance under FISA violated the probable-cause requirement of the Fourth Amendment.