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The DC Circuit Court of Appeals, in a 2-1 ruling, decided the case Friday morning, related to a subpoena of eight years of Trump’s accounting records from his longtime accountant Mazars USA.

The appeals court's opinion broadly supported the House's power to subpoena information about Trump as it investigates him and considers laws in response.

"A congressional committee, as committees have done repeatedly over the past two centuries, issued an investigative subpoena, and the target of that subpoena, questioning the committee’s legislative purpose, has asked a court to invalidate it. The fact that the subpoena in this case seeks information that concerns the President of the United States adds a twist, but not a surprising one," the court wrote. "Having considered the weighty interests at stake in this case, we conclude that the subpoena issued by the Committee to Mazars is valid and enforceable."

The decision marks the first major case where an appeals court has weighed in on the ongoing standoff between the House and Trump. Trump has lost all of his challenges so far that have been decided at the trial-court level to stop House subpoenas.

"Just as a congressional committee could not subpoena the President’s high school transcripts in service of an investigation into K-12 education, nor subpoena his medical records as part of an investigation into public health, it may not subpoena his financial information except to facilitate an investigation into presidential finances" the Court wrote.

"We conclude that in issuing the challenged subpoena, the Committee was engaged in a 'legitimate legislative investigation,' rather than an impermissible law-enforcement inquiry."

The court, in its ruling, cites not only past cases settled by the Supreme Court, but also the history of past President's financial disclosures.

In a dissenting opinion, Trump-appointee Judge Neomi Rao wrote about impeachment, saying "Allowing the Committee to issue this subpoena for legislative purposes would turn Congress into a roving inquisition over a co-equal branch of government."

Though the court's decision was split, the case is widely considered to be a tough one for Trump, even with support from the Justice Department.

He may appeal to the Supreme Court to stop Mazars, but courts including the Supreme Court previously have refused to curtail Congress' subpoena power.

"We detect no inherent constitutional flaw in laws requiring Presidents to publicly disclose certain financial information. And that is enough," the Circuit Court noted.