President Donald Trump lost an appeal Friday to prevent a House subpoena demanding eight years of his tax records from his accountant Mazars USA.

In a 2-1 ruling, the U.S. Court of Appeals for the District of Columbia Circuit upheld a lower court decision that the accounting firm must turn over Trump’s tax returns.

The appeals court called the House subpoena “valid and enforceable.”

“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,” wrote the majority. “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.”

Trump’s legal team had previously sued Mazars USA in an attempt to block another subpoena for his tax returns.

Trump lawyers argued that any criminal investigation into a sitting president is unconstitutional, and they cannot be subject to criminal investigations until they leave office.

While he may appeal the case to the Supreme Court, the appellate court’s decision is a groundbreaking win for Democrats anxious to see Trump’s tax returns.

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“We detect no inherent constitutional flaw in laws requiring Presidents to publicly disclose certain financial information. And that is enough,” the majority opinion stated.

During his 2016 campaign, Trump promised to release his tax returns but has now adamantly reversed his decision. He is the first president since Richard Nixon to keep his taxes completely private.