Donald Trump with Russian Foreign Minister Sergey Lavrov and Russian Ambassador Sergey Kislyak in the White House, May 10, 2017

The FBI is so concerned about Donald Trump’s behavior that it began an investigation in May 2017 about his possible work for Russia against US interests.

The agency started the inquiry after Trump fired FBI Director James Comey, in an attempt to halt the Trump-Russia investigation, and bragged to Russian Foreign Sergey Lavrov about his dismissal of the “nut job”, according to “former law enforcement officials and others familiar with the investigation“.

The FBI also examined if Trump obstructed justice, a possible criminal charge which is now part of Special Counsel Robert Mueller’s Trump-Russia inquiry.

The sources said senior FBI officials were suspicious of Trump’s ties to Russia during the 2016 campaign but deferred an investigation, in part because they were uncertain how to proceed with an unprecedented inquiry of such sensitivity. But Trump’s actions before and after Comey’s firing, as Trump acknowledged it was linked to the Russia investigation, prompted the counter-intelligence operation.

Speical Counsel Mueller was appointed days later and took over the inquiry. It is unclear if Mueller is still pursuing the counter-intelligence dimension, in conjunction with his examination of possible criminal activity.

James A. Baker, FBI General Counsel until late 2017, told House investigators in October, “Not only would [Trump’s firing of Comey] be an issue of obstructing an investigation, but the obstruction itself would hurt our ability to figure out what the Russians had done, and that is what would be the threat to national security.”

Trump lawyer Rudy Giuliani insisted there was no significance in any counter-intelligence investigation: “The fact that it goes back a year and a half and nothing came of it that showed a breach of national security means they found nothing.”

Suspicions from July 2016

The FBI conducts both criminal and counterintelligence investigations. Unlike criminal investigations, which aim to solve a crime and punish perpetrators, counterintelligence inquiries seek to understand what a foreign power is doing and to stop activity such as thefts of Government material or covert efforts to influence American policy.

The concern of FBI counter-intelligence agents was raised in July 2016 when Trump called on Russia to hack the e-mails of Democrat nominee Hillary Clinton.

Agents also noted that Trump refused to criticize Russia and praised President Vladimir Putin. Worries grew when the Republican Party, reportedly at the urging of Trump staff, softened its convention platform on Russia’s annexation of Crimea and encouragement of the breakup of Ukraine.

The FBI had been investigating one Trump campaign advisor, Carter Page, since 2013 as a possible Russian agent. Investigations were opened in 2016 into three other Trump associates.

FBI reservations over an inquiry into Trump were finally set aside by two Trump acts after his firing of Comey on May 9, 2017.

The first was a letter that Trump intended to send to Comey about the dismissal, in which Trump thanked Comey for previously telling him that he was not a subject of the Trump-Russia investigation.

Deputy Attorney General Rod Rosenstein, revising the draft, told Trump that he did not have to mention the Russia investigation. But Trump directed Rosenstein to refer to it, an order Rosenstein disregarded.

The second development was Trump’s declaration on May 11, in an NBC News interview:

I was going to fire Comey knowing there was no good time to do it. And in fact, when I decided to just do it, I said to myself — I said, you know, this Russia thing with Trump and Russia is a made-up story. It’s an excuse by the Democrats for having lost an election that they should’ve won.

FBI officials worried that Trump would appointed an FBI Director who might slow down or even halt the Russia investigation.

Those worries were reinforced when Trump told Russian Foreign Minister Sergey Lavrov and Russian Ambassador Sergey Kislyak, “I just fired the head of the F.B.I. He was crazy, a real nut job. I faced great pressure because of Russia. That’s taken off.”