(CNN) — The House Judiciary Committee is suing two Justice Department tax prosecutors involved in the Hunter Biden criminal investigation whom Republicans have been trying to interview for months, ratcheting up a separation of powers fight between Congress and the Biden administration that is now spilling into court.

The Republican-led committee filed the lawsuit in Washington, DC’s federal court against federal tax prosecutors Mark Daly and Jack Morgan. The committee has been demanding the men testify as part of its impeachment inquiry around the Biden family since September.

The complaint asked the court on Thursday to step in immediately with an emergency order that would force Morgan and Daly to testify. That outcome is unlikely, however, as lawsuits like these typically are part of political tactics in standoffs between Congress and the executive branch when they are controlled by opposing political parties.

Republicans have wanted to talk to these two officials as part of their probe into the DOJ’s handling of the criminal case of the president’s son, specifically wanting to ask Morgan and Daly about meetings and conversations among federal investigators and about the Departments’ protracted decision-making before charging Hunter Biden for tax avoidance. Republicans zeroed in on these two career prosecutors after IRS whistleblowers alleged that Daly and Morgan were supportive of charging the president’s son for tax crimes then changed their recommendations.

An attorney for Daly declined to comment about the lawsuit, and an attorney for Morgan didn’t immediately respond to a request from CNN on Thursday. The Justice Department is likely to represent the two DOJ officials in court to oppose the lawsuit.

Federal District Judge Ana Reyes, a Biden appointee, is assigned to handle the lawsuit, according to court records.

Justice Department blocking testimony

The Department of Justice has so far repeatedly told the House the DOJ wouldn’t allow these employees to testify about their official work, and that the subpoenas were invalid, according to letters with the committee released as part of the lawsuit. The House had said Justice Department lawyers couldn’t sit in on the depositions of the DOJ prosecutors — a rule the Justice Department took particular issue with.​

“They defied the Subpoenas because they elected to comply with DOJ’s baseless and unlawful direction not to appear,” lawyers for the House wrote in the lawsuit Thursday. “Regardless of what information Daly and Morgan will disclose, or who may accompany them, they still must appear.”

The Justice Department has refused to make Daly and Morgan available for depositions, instead allowing more senior officials overseeing the Hunter Biden criminal investigation to testify. The Department also objected to the career prosecutors testifying because of taxpayer privacy, secrecy protections around criminal investigations and constitutional concerns related to the separation of powers between Congress and the executive branch, according to letters made public in the House lawsuit.

“The constitutional and statutory questions raised by the competing claims of the executive and legislative branches of government in instances like this are thorny, complex, and in many instances unresolved by the third branch of government—the courts,” Daly’s attorney Robert Driscoll wrote in one letter to the committee last fall. “I urge a negotiated resolution between the committee and DOJ … It is not up to Mr. Daly.”

A lawyer for Morgan, Catherine Duval, also told the committee Morgan would be “following his employer’s directive,” according to the court records.

A Justice Department spokesperson defended the decision to block Morgan and Daly from testifying, telling CNN Thursday that it will “continue to protect our line personnel and the integrity of their work” and respond to the filings in court.

“The Department is committed to working with Congress in good faith,” the spokesperson said. “It is unfortunate that despite this extraordinary cooperation from senior DOJ officials, the Committee has decided, after waiting for months, to continue seeking to depose line prosecutors about sensitive information from ongoing criminal investigations and prosecutions.”

Courts unlikely to end standoff

This is the second time the Republican-led House in the current Congress has gone to court in an attempt to enforce subpoenas of witnesses.

Earlier this year, the Judiciary Committee sued for an FBI agent’s testimony in an investigation of the Biden administration over its approach to tech companies and online speech. That lawsuit is still in its earliest stage.

The cases follow in the footsteps of a major court fight over House testimony from the former Trump White House counsel Don McGahn as part of the Russia investigation. The case generated many headlines for years and several judicial opinions. But it ended in a whimper with McGahn agreeing to testify years later, after Trump left the presidency.

Historically, Congressional subpoena lawsuits end unsuccessfully when a court is asked to intervene – and instead typically end with a negotiated agreement between the executive branch and Congress.

The McGahn subpoena standoff came closest among any lawsuit to getting the courts to define Congress’ subpoena power. But there isn’t binding law from the federal judiciary on whether the House has given itself the ability to sue to enforce its subpoenas.

(Copyright (c) 2024 CNN. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

Join our Newsletter for the latest news right to your inbox