Democrats have urged the appeals court to rule quickly in a bid to determine whether the former Trump aide has evidence that could be folded into their presentation at the upcoming Senate trial that will determine whether the president should be removed from office or to assist them in drafting additional articles of impeachment.

Democrats seeking Trump’s tax information said the November ruling buttressed their arguments that McFadden should reject pleas by the president’s lawyers to dismiss their suit.

House Ways and Means Chairman Richard Neal (D-Mass.) is suing under a 1924 law allowing the heads of Congress’ tax committees to examine anyone’s private tax information.

The case is still in its early stages, and Trump lawyers are demanding that it be dismissed, arguing that the court doesn’t have jurisdiction over fights between Congress and the White House over information.

In the McGahn case, a three-judge panel heard oral arguments earlier this month, and a ruling is possible by the end of this month.

The Justice Department is appealing a decision backing Judiciary Democrats who want to question McGahn under oath about what he witnessed in the White House in connection to Trump’s efforts to stymie special counsel Robert Mueller’s probe into Russian election interference in 2016.

The Justice Department argues that McGahn, like many other government officials, has “absolute immunity” from speaking to congressional investigators. In addition, the department has urged the court to avoid getting involved in any dispute between the other two branches of government.

But there may not be such a fast resolution to the McGahn fight. Whoever loses the case before the three-judge panel is likely to appeal that decision, first to the entire D.C. Circuit panel of judges and ultimately to the Supreme Court. And even if the courts order McGahn to testify, the Trump administration would have the option of drawing out the process even longer by asserting executive privilege over specific questions posed by Democratic investigators.

That drawn-out process could mean Neal’s suit — one of several legal fights over access to information about Trump’s finances, including a couple of cases headed to the Supreme Court in March — will be on hold for a considerable period of time.