Gregory Katsas testifies before the Senate Judiciary Committee during his confirmation hearing to be a judge at the U.S. Court of Appeals for the D.C. Circuit, on Oct. 17, 2017. Diego M. Radzinschi/ALM

The U.S. Court of Appeals for the D.C. Circuit on Wednesday rejected President Donald Trump's request for an en banc rehearing of the case challenging a congressional subpoena to his personal accounting firm Mazars, sending the case on a direct path to the U.S. Supreme Court.

In a per curiam order, the circuit court said a majority of the judges were against an en banc rehearing of the case. Three judges—Neomi Rao, Gregory Katsas and Karen Henderson—said they would have granted the petition for rehearing.

This means that two cases relating to the president are now prepared to go to the Supreme Court after Trump's lawyers said they will go to the high court over whether Manhattan District Attorney Cyrus Vance can obtain Trump's state tax returns.

This will be the first case over the congressional subpoenas issued for Trump's records to go to the Supreme Court. And it will land in the justices' hands on the backdrop of the House's current impeachment inquiry into Trump.

The Supreme Court has long been the target of Trump's attorneys, which include Consovoy McCarthy lawyer William Consovoy and former White House lawyer Stefan Passantino, now with Michael Best & Friedrich.

In a ruling last month, a three-judge panel on the D.C. Circuit ruled 2-1 in favor of upholding the subpoena. Rao was one of the judges on the panel, and authored a dissenting opinion against the subpoena. She wrote at the time that the subpoena needed to fall under the scope of an impeachment investigation, which was not occurring at the time the subpoena was issued.

In her dissenting opinion issued Wednesday, Rao said the Mazars case should be reheard en banc for "the reasons expressed in my dissent to the panel opinion."

"Investigations of impeachable offenses simply are not, and never have been, within the legislative power because impeachment is a separate judicial power vested in Congress," Rao wrote. "The panel's analysis of these issues misapprehends the gravamen of the committee's subpoena and glosses over the difficult questions it raises for the separation of powers."

Rao said the House's current impeachment inquiry doesn't necessarily resolve the issues she identified with the subpoena, because the subpoena was not initially part of that inquiry. The judge wrote that a House resolution passed after the subpoena was issued may have addressed those flaws, but noted that the D.C. Circuit "has not determined whether a defective subpoena can be revived by after-the-fact approval."

In a separate dissent, Katsas wrote the case "presents exceptionally important questions regarding the separation of powers among Congress, the Executive Branch, and the Judiciary."

And he said that, under the argument made by the majority panel in upholding the subpoena, it could "create an open season on the president's personal records."

"This threat to presidential autonomy and independence is far greater than that presented by compulsory process issued by prosecutors in criminal cases, as in United States v. Nixon, or even by private plaintiffs in civil cases, as in Clinton v. Jones," Katsas wrote.

Henderson joined on both Katsas and Rao's dissenting opinions.

Read the order:

Read more:

Trump Lawyers Set the Stage for Supreme Court to Rule on Mazars Subpoena

DC Circuit Upholds Democrats' Subpoena for Trump's Financial Records

After Circuit Court Loss, Trump's Lawyers Could Delay a Final Ruling in Dems' Subpoena Case

After Speedy Subpoena Cases, Trump Tax Disputes Linger