Mueller is serious business.
WASHINGTON — The special counsel, Robert S. Mueller III, removed a top F.B.I. agent from his investigation into Russian election meddling after the Justice Department’s inspector general began examining whether the agent had sent text messages that expressed anti-Trump political views, according to three people briefed on the matter.
The agent, Peter Strzok, is considered one of the most experienced and trusted F.B.I. counterintelligence investigators. He helped lead the investigation into whether Hillary Clinton mishandled classified information on her private email account, and then played a major role in the investigation into links between President Trump’s campaign and Russia.
But Mr. Strzok was reassigned this summer from Mr. Mueller’s investigation to the F.B.I.’s human resources department, where he has been stationed since. The people briefed on the case said the transfer followed the discovery of text messages in which Mr. Strzok and a colleague reacted to news events, like presidential debates, in ways that could appear critical of Mr. Trump.
A lawyer for Mr. Strzok declined to comment. A spokeswoman for the Justice Department said that “we are aware of the allegation and are taking any and all appropriate steps.”
Mr. Strzok’s reassignment shows that Mr. Mueller moved swiftly in the face of what could be perceived as bias by one of his agents amid a politically charged inquiry into Mr. Trump’s campaign and administration. But the existence of the text messages is likely to fuel claims by Mr. Trump that the F.B.I. has a bias against him and that he is a target of the “deep state” — a term used to describe the notion that government intelligence agencies secretly conspire together.