President Donald Trump waves good-bye as he boards Air Force 1. Credit: White House

The next key fight over President Donald Trump's financial records could be whether it gets resolved by the U.S. Supreme Court before the end of Trump's first term in office.

The Oct. 11 2-1 decision upholding a congressional subpoena for Trump's financial records from his accounting firm Mazars marked the second time a court has ruled in favor of House Democrats in the case. The ruling likely tees up a request from the president for an en banc hearing at the U.S. Court of Appeals for the D.C. Circuit before the case gets to the justices, a process that could potentially drag out for more than a year.

Saikrishna Prakash, a law professor at the University of Virginia, said Trump's attorneys using procedural hurdles, like requesting an en banc rehearing, would fit within their general legal strategy of delay.

If Democrats were to lose control of the House in the 2020 elections, the chances of Republicans continuing with the vast investigations into Trump, his finances and his administration are slim to none.

"You want to stretch things out because your adversaries may go away, or their order to investigate may go away," Pravash said.

The Mazars case has moved relatively quickly for litigation, with a district judge ruling for the House just weeks after the initial complaint was filed, and the circuit court agreeing to expedited briefing.

However, the panel took almost exactly three months from the day oral arguments were held—and about two months after briefing ended on the DOJ's stance on the case—to write and issue the lengthy opinion.

And Trump's lawyers also have up to 45 days after the ruling to request an en banc rehearing. (The normal time period is 30 days, but cases where the federal government is a party get an extension.)

The Supreme Court has appeared to be the ultimate goal for Trump attorneys in several of the lawsuits. Trump's private attorneys have argued against precedent that has bound lower courts, meaning only a higher body could overturn those opinions.

And the lawyers have targeted the justices well before the case was set to reach their bench: For example, in one filing in the Mazars case in D.C. District Court, the president's attorneys argued that allowing access to Trump's financial records would also expose Supreme Court justices to the same level of scrutiny.

"Replace 'president' with 'justices' and the ruling below would, without question, authorize a congressional subpoena for the justices' accounting records—even for many years before they joined the court," Trump's lawyers argued to the circuit panel in one brief, urging them to overturn the district court. William Consovoy of Consovoy McCarthy and former White House lawyer Stefan Passantino of Michael Best & Friedrich signed the filing.

A decision by the D.C. Circuit to take up the case en banc would further delay a resolution, and a decision to reject the request would by no means guarantee a speedy resolution at the Supreme Court.

The panel's order said the documents could be turned over seven days after the deadline to petition for a rehearing passes. Barring an en banc hearing, Trump's lawyers could ask for an emergency stay from either the D.C. Circuit or the Supreme Court to block the subpoena from being enforced.

The president's attorneys would also get 90 days to file a petition for writ of certiorari with the Supreme Court, meaning it could be months before briefing begins on whether the justices should take up the case.

The justices' deliberations take place behind closed doors and few details are made available about the court's secret proceedings, making it anyone's guess as to how quickly the court could decide on the petition. They could swiftly schedule it for the end of their term, as they did with a case on the census citizenship question, or push it off until the next term, about a year from now.

University of Chicago Law professor Daniel Hemel argued in a piece for The Washington Post on Monday that the justices could easily push a final ruling on the case until after the 2020 election.

"By the time the court releases its opinion, Trump either could have already taken the oath of office a second time, or he could be out of the White House and licking his electoral wounds at his Mar-a-Lago resort," Hemel wrote. However, he urged the justices "to put the case on a much faster timetable and resolve it well before voters must decide whether to reelect the president."

Legal experts say some factors, like the end of the House's term in 2021 and the ongoing impeachment inquiry, could push the courts to rule more swiftly.

Marty Lederman, a constitutional law professor at Georgetown University, said that while the subpoena wasn't initially issued for the purposes of an impeachment inquiry, a court could accelerate the timeline for resolving the case if the House introduces the inquiry as another ground for the subpoena. For example, the financial documents could reveal potential conflicts of interest between Trump and foreign entities.

House Democrats have not yet raised impeachment in the Mazars proceedings, as the inquiry hadn't formally started when the lawsuit was filed. The case has focused on the House's right to get the financial documents as part of its oversight powers.

D.C. Circuit Judge Neomi Rao, who ruled against the subpoena, argued in her dissenting opinion that impeachment is the only process through which Congress can obtain documents from the executive branch that could reveal impeachable offenses.

"Invoking the impeachment inquiry might make some judges more inclined to expedite the case," Lederman said.

Lederman added that because the membership of the House changes every two years, there's a compelling argument for courts to rule promptly on this case, "so the House has enough time to take full account of what it learns and to take appropriate steps, if any, during its session."

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