03 Don McGahn FILE
CNN  — 

The House Judiciary Committee told a federal appellate court on Wednesday that it would reissue its subpoena to Don McGahn in the next Congress, almost two years after it first sought the former White House counsel’s testimony about witnessing attempts by President Donald Trump to obstruct justice during the Mueller investigation.

The pledge to re-subpoena McGahn keeps alive not only the congressional inquiry into Trump, but also a protracted court battle where the House has sought a court order that would give it more power to enforce its subpoenas.

The court fight, now in its fourth round at the DC Circuit Court of Appeals, has taken on major questions about separation of powers between an aggressively investigating Congress and a noncompliant White House and about the federal judiciary’s ability to address interbranch standoffs.

The House also wants the full circuit court to reject a Trump administration approach of claiming “absolute immunity” for its officials, which has allowed it to ignore multiple subpoenas in major Trump congressional investigations, including ones related to then-Special Counsel Robert Mueller’s obstruction probe and during Trump’s impeachment hearings.

“The Committee maintains a right to and need for McGahn’s testimony. The Committee, whose Chairman will not change in the next Congress, will reissue the subpoena, consistent with House Rules and precedent. This case will thus continue, and nothing about the end of this Congress will prevent this Court from resolving it,” the House committee wrote on Wednesday.

The McGahn case isn’t the only one that House Democrats plan to keep alive after Trump leaves office. They also intend to pursue other Trump-related cases, including efforts to obtain his tax returns, Mueller’s grand jury material and Trump’s financial documents.

Republican Rep. Jim Jordan of Ohio, the committee’s ranking member, said in a letter on Wednesday that Republicans opposed re-subpoenaing McGahn and criticized Chairman Jerry Nadler, a New York Democrat, for having a “fanatical obsession with attacking” Trump.

Mueller, in documenting several instances of possible obstruction by Trump as the President sought to shut down the Russia investigation, often relied on McGahn’s testimony. But McGahn never described what he had witnessed outside of closed-door interviews with the FBI and prosecutors.

Ultimately, the special counsel outlined on multiple occasions how Trump’s behavior met the legal standard for an obstruction case. But, partly because of Justice Department policy that bars indicting a sitting president, Mueller left the choice on whether to indict Trump to the attorney general, and handed a report to Congress. Trump was not indicted.

The House did little to push an investigation into Trump based on Mueller’s obstruction findings, largely because the McGahn subpoena case and other lawsuits prompted by Trump and his Justice Department bogged investigative steps down in court.

Jeremy Herb contributed to this story.