First things first: ♦Understand Obama’s Surveillance Operation HERE. ♦Michael Flynn wasn’t under a FISA (Title-1) HERE …. that’s the background.
The riddle of how the White House discovered the telephone call and subsequent content between Michael Flynn and Russian Ambassador Sergey Kislyak appears to have been solved. The FBI used a “Pen Register.” There was no unmasking, and no warrant.
A pen register is a device/process which records the telephone numbers of outgoing calls. Monitoring outgoing call numbers does not require a search warrant or FISA.
After the 2016 election Lt. Gen Flynn was given a government issued secure cell phone; a blackberry device for use. However, with Flynn under a preexisting FBI investigation the phone numbers Flynn was calling in December ’16 and January ’17 were being monitored.
A review of prior testimony by former FBI Director James Comey [HERE]; prior testimony by former Deputy Director Andrew McCabe [Here]; and a cross-reference of recent releases of Flynn unmasking documents [Here] tells the full story.
In December of 2016 incoming National Security Advisor Michael Flynn was under a sketchy FBI Counterintelligence investigation for possible coordination with Russia. According to recent documents and the Comey transcript, the Flynn investigation began in the summer of 2016; that investigation was ongoing in late December.
After President Obama initiated sanctions against Russia on December 29, 2016. The Obama administration was trying to figure out why Russia was not reacting. According to James Comey testimony the intelligence community, writ large, was tasked to find out why Russia was not reacting more severely. See Transcript:





