On August 1, 2002, Collyer was nominated by President George W. Bush to a seat on the United States District Court for the District of Columbia vacated by Thomas Penfield Jackson. Collyer was confirmed by the United States Senate on November 14, 2002, and received her commission on November 15, 2002. She assumed senior status on May 18, 2016. In 2013, Collyer was appointed by the Chief Justice of the United States to a seven-year term on the Foreign Intelligence Surveillance Court. The Court provides a measure of judicial oversight over surveillance activities under the Foreign Intelligence Surveillance Act, as amended. Judge Collyer's term on the FIS Court began on March 8, 2013 and was set to conclude on March 7, 2020. She replaced Judge John D. Bates, whose term ended on February 21, 2013. On December 20, 2019, she announced she will continue to serve out her full seven year term on the FISC, not as the Presiding Judge FISC due to health reasons ending on December 31, 2019 and replaced by FISC Judge James E. Boasberg elevated to preside.
Notable cases
Judge Collyer presided over a number of habeas corpus petitions submitted on behalf of Guantanamo captives. In United States House of Representatives v. Price, Judge Collyer first found the House had standing to sue the Obama Administration and, then, found that the Administration had unconstitutionally spent billions of Treasury funds on health insurer subsidies without a Congressional appropriation. Judge Collyer enjoined any further insurer reimbursements without a valid appropriation, but stayed her order pending appeal. Collyer was one of four FISA Court judges who approved a FISA warrant authorizing the wiretapping of Carter Page. In December 2019 Collyer issued an order saying the FBI "provided false information to the National Security Division of the Department of Justice, and withheld material information from NSD which was detrimental to the FBI's case, in connection with four applications to the Foreign Intelligence Surveillance Court for authority to conduct electronic surveillance of a U.S. citizen named Carter W. Page" ordering the government to inform the court of planned procedures to "ensure that the statement of facts in each FBI application accurately and completely reflects information possessed by the FBI that is material to any issue presented by the application."
