The House of Representatives is looking into whether President Trump lied to former special counsel Robert Mueller, an attorney representing the House Judiciary Committee told a federal court Monday.

Doug Letter, an attorney representing the committee, confirmed this to a panel of three circuit judges Monday. When U.S. Court of Appeals for D.C. Judge Thomas Griffith asked Letter what the congressional committees conducting the House impeachment inquiry want to do with investigation documents from Mueller's investigation, Letter explained the committees are probing two matters — one related to Ukraine, and the other on whether or not the president lied to Mueller during his investigation. Mr. Trump submitted written answers to Mueller as a part of the special counsel's probe into Russian election interference and any involvement of Trump campaign associates.

Mueller determined Russians had interfered extensively in the 2016 presidential election, but he did not find enough evidence to indict Trump associates for any coordination with that disinformation campaign.

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On Monday morning, Mr. Trump suggested he might submit testimony in the new investigation casting a shadow on his presidency — the House's impeachment inquiry.

"Speaker of the House, Nervous Nancy Pelosi, who is petrified by her Radical Left knowing she will soon be gone (they & Fake News Media are her BOSS), suggested on Sunday's DEFACE THE NATION ... that I testify about the phony Impeachment Witch Hunt," the president tweeted Monday morning. "She also said I could do it in writing. Even though I did nothing wrong, and don't like giving credibility to this No Due Process Hoax, I like the idea & will, in order to get Congress focused again, strongly consider it!"