Question for better informed anons:

Is there anything related to FISA that would preclude it from being used to surveil members of law enforcement that had contact with someone under FISA surveillance?

For example, Peter Strzok interviews Mike Flynn, who was the subject of a FISA warrant, making Strzok now a contact one hop out from Flynn and making Strzok’s personal network of contacts the second hop out. Under FISA, would any surveillance, mapping, tracking and data mining of Strzok’s network of contacts (two hops out under FISA) have been completely lawful and permissible?

FISA goes both ways. Would it potentially have put elements of the FBI/CIA under lawful umbrella surveillance?