Joshua Matz of Kaplan Hecker & Fink.

The House Judiciary Committee is tapping a top legal scholar on impeachment as it prepares for its expanded role in the impeachment inquiry.

Kaplan Hecker & Fink of counsel Joshua Matz is the latest attorney to be added to the committee's legal team. Matz, who has been involved in several high-profile lawsuits against the Trump administration, is an expert on impeachment, offering legal expertise and firepower to the committee as it prepares for its role in impeachment proceedings.

A committee spokesperson on Wednesday confirmed the hire.

A message sent from Matz's law firm email address said he is taking a "short term leave-of-absence" to "work on a matter in the public interest." Matz, who did not respond to a request for comment, is no longer listed on Kaplan Hecker's staff page.

House Judiciary Committee chairman Jerrold Nadler declined to comment Wednesday when asked about Matz's hire.

Rep. Sheila Jackson Lee, a member of the Judiciary Committee, also declined Tuesday to say whether Matz had been hired.

However, she emphasized the need for the committee to have expertise on its side as it moves forward with impeachment proceedings.

"We want to make sure that as our work continues, the American people see that we are somber and sober, and that we have the most efficient way forward," said Lee, a Democrat. "And that will entail a great deal more expertise."

Matz is an expert in presidential impeachments, a relatively obscure area of law. He, along with Harvard Law's Laurence Tribe, last year published the book, "To End a Presidency: The Power of Impeachment."

Matz is joining Citizens for Responsibility and Ethics in Washington's Norm Eisen and Kramer Levin Naftalis & Frankel's Barry Berke as legal hires by the panel, as the committee prepares for the key role of potentially drafting articles of impeachment.

Eisen and Berke have worked on the House Judiciary Committee's lawsuits seeking grand jury materials redacted from the Mueller report and compelling former White House counsel Don McGahn's testimony. Both attorneys attended a hearing last week on the grand jury information, but did not sit at the counsel's table as House general counsel Douglas Letter's team took the lead in court.

Berke also earned praise for his questioning of former Trump campaign manager Corey Lewandowski during an impeachment inquiry hearing last month.

Matz is no stranger to legal fights involving the Trump administration. He has represented constitutional law scholars as an amicus party backing the House Ways and Means Committee's lawsuit seeking Trump's federal tax returns.

And he was also on the Maryland and D.C. attorneys general's Emoluments Clause lawsuit filed against Trump, where he is listed as an attorney for legal historians who opposed the Justice Department's stance in the case.

Matz filed a motion to withdraw from the tax returns case on Tuesday.

Matz joined Kaplan as a counsel from the boutique firm Gupta Wessler. He is also an adjunct professor at Georgetown Law, where his bio calls him "an expert in constitutional law, civil rights, and presidential impeachment."

The ongoing impeachment inquiry has been headed by the House intelligence, oversight and foreign affairs committees. Staff are handling the questioning of key witnesses, opening the door for lawyers from all three committees to be involved.

Letter, the House general counsel, has also occasionally turned to outside firms to help with the House's lawsuits, most recently in the court case over the subpoena for Trump's financial records from his accounting firm Mazars.

Roy Englert, Jennifer Windom and Alan Strasser, from the firm Robbins, Russell, Englert, Orseck, Untereiner & Sauber, filed their notice of appearance Tuesday shortly after they appeared on a brief in the U.S. Court of Appeals for the D.C. Circuit.

Speaker Nancy Pelosi has tasked each of the House's six committees with determining its best case for impeaching Trump. Those results will then be referred to the House Judiciary Committee, which will comb through the evidence and draft any articles of impeachment, if necessary.

It's that process that Matz is most likely to play a role in, as the bulk of investigating potential wrongdoing has shifted away from the Judiciary Committee.

Democrats on the panel have been discussing potential staffing for their role of the impeachment proceedings. Bringing on a whole new team of attorneys to handle impeachment, as was done for the committee's work on the Nixon impeachment inquiry, is among the options being floated among the Democratic caucus.

Fellow House Judiciary Committee Democrat David Cicilline said Tuesday he too did not know of Matz's hiring at the time.

"I think there have been some general discussions about whether or not we will need to hire additional counsel as we move forward," he said, "but I'm not familiar with that particular person."

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