Russia Carter Paige
A FISA warrant was granted against Carter Page, an early adviser to Donald Trump's presidential campaign. (Photo: Reuters)

At the center of President Trump's latest conspiracy theory is a FISA warrant, which was granted against an early foreign-policy adviser to his campaign, Carter Page. The FBI applied for — and was granted — the FISA against Page because they had observed him interacting with Russian intelligence officers and worried that he was susceptible to being recruited as a Russian asset. To Trump, that was more evidence of a "witch hunt."

What does FISA stand for?

FISA stands for Foreign Intelligence Surveillance Act, which was passed in 1978 and created the FISA process, the FISA Court and guidelines for wiretapping suspected spies.

What do FISA warrants do?

A FISA warrant allows authorities to wiretap someone who is suspected of spying with or for a foreign government. It must be approved by a judge on the FISA Court. The 11-judge tribunal is selected by the Chief Justice of the Supreme Court and has the authority to grant warrants for electronic surveillance.

A FISA warrant allows for wiretapping a "foreign power or an agent of a foreign power." It's requested by U.S. authorities or intelligence agents, and usually signed by the attorney general. The requesting authorities have to jump through a number of hoops to obtain a FISA warrant or to have it renewed: They have to prove that the facility to be bugged is being used by someone connected to a foreign power or agent. The warrant is usually valid for 12 months. In order for it to be renewed, the authorities have to prove that the information that has been gathered under the warrant is relevant.

 

The FISA court is closed to the public and its actions are secret, which has given space for Trump and his defenders to foment a conspiracy theory about the warrant against Page. They claim that the initial application was based on the "Steele dossier" (which began as opposition research against the Trump campaign funded by a conservative newspaper, then Republican Sen. Ted Cruz, then the Clinton campaign) and was therefore partisan, so the entire investigation should be dismissed.

The 412 pages of documents released by the Justice Department showed that the warrant was based on information gained by an FBI investigation of Page, when began when he became known to them by allegedly interacting with Russian intelligence officers in 2013. A FISA warrant against Page was approved in 2016 and renewed three times, all by Republican judges. As released last week, the renewal applications are heavily redacted, but each one is larger than the last.