House Intelligence Committee chairman Devin Nunes has issued an angry demand to the FBI and Department of Justice to explain why they kept the committee in the dark over the reason Special Counsel Robert Mueller kicked a key supervising FBI agent off the Trump-Russia investigation.

Stories in both the Washington Post and New York Times on Saturday reported that Peter Strzok, who played a key role in the original FBI investigation into the Trump-Russia matter, and then a key role in Mueller's investigation, and who earlier had played an equally critical role in the FBI's Hillary Clinton email investigation, was reassigned out of the Mueller office because of anti-Trump texts he exchanged with a top FBI lawyer, Lisa Page, with whom Strzok was having an extramarital affair. Strzok was transferred to the FBI's human resources office — an obvious demotion -- in July.

The Post reported that Strzok and Page exchanged text messages that "expressed anti-Trump sentiments and other comments that appeared to favor Clinton."

Word of the messages and the affair were news to Nunes, even though the committee had issued a subpoena that covered information about Strzok's demotion more than three months ago. The committee's broadly worded subpoena for information related to the so-called Trump dossier went to the FBI and DOJ on Aug. 24. In follow-up conversations on the scope of the subpoena, committee staff told the FBI and DOJ that it included information on the circumstances of Strzok's reassignment.

On Oct. 11, Nunes met with deputy attorney general Rod Rosenstein. In that meeting, Nunes specifically discussed the committee's request for information about Strzok.

In an Oct. 31 committee staff meeting with the FBI, bureau officials refused a request for information about Strzok.

On Nov. 20, the committee again requested an interview with Strzok. (Three days earlier, on November 17, Strzok met with the Senate Intelligence Committee.)

On Nov. 29, Nunes again spoke to Rosenstein, and again discussed Strzok.

On Dec. 1, the committee again requested to speak with Strzok.

After each occasion, the FBI and DOJ did nothing. Now, in what appears to be an orchestrated leak, both the Post and Times published the reason for Strzok's demotion, along with concerns that the revelation might help President Trump. "Among federal law enforcement officials, there is great concern that exposure of the texts they exchanged may be used by the president and his defenders to attack the credibility of the Mueller probe and the FBI more broadly," the Post reported. The Times reported that "the existence of the text messages is likely to fuel claims by Mr. Trump that he is the target of a witch hunt."

Well, yes. It will be of concern to Trump's defenders, and to defenders of fair investigations generally, that such an important figure in both the Clinton and Trump probes privately expressed bias. It will be important for investigators -- and the public -- to see Strzok's and Page's texts to assess the extent of the problem. But in any event, Nunes is extremely unhappy -- not only with the revelation of bias but with the FBI's resistance.

"By hiding from Congress, and from the American people, documented political bias by a key FBI head investigator for both the Russia collusion probe and the Clinton email investigation, the FBI and DOJ engaged in a willful attempt to thwart Congress' constitutional oversight responsibility," Nunes said in a statement Saturday afternoon. "This is part of a months-long pattern by the DOJ and FBI of stonewalling and obstructing this committee's oversight work, particularly oversight of their use of the Steele dossier. At this point, these agencies should be investigating themselves."

To add insult to injury, at just the moment the leaked stories appeared, the Justice Department out of the blue notified Nunes that it would meet some of the committee's demands for information that it had been refusing for months. That didn't make the chairman happy, either.

"The DOJ has now expressed -- on a Saturday, just hours after the press reports on Strzok's dismissal appeared -- a sudden willingness to comply with some of the committee's long-standing demands," Nunes said in the statement. "This attempted 11th-hour accommodation is neither credible nor believable, and in fact is yet another example of the DOJ's disingenuousness and obstruction."

As a result, Nunes said he has instructed committee staff to draw up a contempt of Congress citation for Rosenstein and for FBI Director Christopher Wray. The chairman promised to take action on the citation before the end of December unless the FBI and DOJ meet all the committee's outstanding demands.

Obviously Nunes is angry that he did not know about the real reasons for Strzok's demotion. And he is equally angry with the FBI's and DOJ's treatment of the committee. Contempt of Congress is a big move for lawmakers to take, especially against an agency controlled by the same party as leaders of the House. But remember, House Speaker Paul Ryan has already said the FBI and DOJ "stonewalled" the House, and he demanded that it comply immediately. That was five weeks ago. Now, after this latest episode, it seems likely that leaders in Congress are becoming increasingly frustrated with what they see as the FBI and DOJ jerking lawmakers around. At some point, they will act.

UPDATE: On Sunday, Justice Department spokeswoman Sarah Isgur Flores sent this statement: "We disagree with the Chairman's characterization and will continue to work with congressional committees to provide the information they request consistent with our national security responsibilities. The Department has already provided members of [the House Intelligence Committee] and House leadership with several hundred pages of classified documents and multiple briefings -- including for example clear answers as to whether any FBI payments were made to a source in question related to the dossier -- and has more recently cleared key witnesses they have requested to testify, including Mr. McCabe, Mr. Strzok, and the alleged handler in question."