A federal judge ruled Wednesday a former New York prosecutor must testify to Congress about investigating Donald Trump, shutting down an attempt by Manhattan District Attorney Alvin Bragg to block the testimony.

U.S. District Judge Mary Kay Vyskocil ruled that Mark Pomerantz would have to testify before the House Judiciary Committee in its investigation of Bragg. She described balancing the politics of a Democratic prosecutor investigating a Republican former president against a Republican congressional inquiry into the probe.

"In our federalist system, elected state and federal actors sometimes engage in political dogfights," Vyskocil, who was appointed by Trump, wrote in her ruling. "The sole question before the Court at this time is whether Bragg has a legal basis to quash a congressional subpoena that was issued with a valid legislative purpose. He does not."

She also said she would hold on to jurisdiction in similar cases if Bragg sought to challenge subpoenas to other witnesses in the Trump investigation.

Bragg's office appealed the decision to the 2nd U.S. Circuit Court of Appeals.

But Vyskocil refused to temporarily halt Pomerantz's testimony while the appeal is decided because she said Bragg is unlikely to win. She ruled Bragg "is not likely to succeed on the merits of any appeal, nor will he be irreparably injured."

Pomerantz was scheduled to testify Thursday.

A committee spokesman said the decision would allow the panel to continue its oversight.

“Today’s decision shows that Congress has the ability to conduct oversight and issue subpoenas to people like Mark Pomeranz, and we look forward to his deposition before the Judiciary Committee," said Russell Dye.

Judiciary Chairman Jim Jordan, R-Ohio, subpoenaed Pomerantz to ask about what he calls a political prosecution of Trump. The former president is charged with 34 counts of falsifying business records to make hush payments to an adult film actress. Pomerantz wrote a book about the investigation before he left Bragg's office more than a year ago.

Bragg sued Jordan to block the subpoena, which he called unconstitutional interference with the case on behalf of Trump. Bragg also instructed Pomerantz not to cooperate with Jordan because of concern he could relay confidential information about the investigation.

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Here is what we know about the case:

What is Bragg's lawsuit about?

The lawsuit characterized Jordan's committee as trying to "second guess the judgment of New York citizens and interfere with the state criminal justice process."

The lawsuit asserts Trump's rhetoric before and after his indictment has prompted threats and Republican lawmakers including House Speaker Kevin McCarthy of California and Rep. Marjorie Taylor Greene of Georgia to launch a campaign of retaliation.

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Bragg's office received more than 1,000 calls and emails from Trump's supporters, including death threats and a package containing a suspicious white powder, according to the lawsuit.

"These statements have had a powerful effect," the lawsuit said. "But rather than denounce efforts to vilify and denigrate the District Attorney and the grand jury process, House Republicans are participating in those efforts."

What is Jordan's position?

Jordan's response to the lawsuit Monday called the strategy “extraordinary and unconstitutional.”

His committee is investigating Bragg because he vowed to investigate Trump as part of his 2021 campaign for Manhattan district attorney, Jordan said in his court filing. The panel held a hearing Monday about crime in New York. And three House Republican chairmen have asked Bragg questions about his inquiry.

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Presidents need to be protected from lawsuits during or after their administrations, to avoid influencing their policy choices, according to Jordan. Lawsuits against lawmakers or their committees or members should also be blocked because they could hinder congressional investigations, according to Jordan.

“Plaintiff District Attorney Alvin Bragg, Jr., seeks extraordinary and unconstitutional relief from this Court to impede a Congressional inquiry by preventing a witness from complying with a duly issued subpoena,” Jordan’s filing said.

This article originally appeared on USA TODAY: Trump New York charges: Judge says ex-prosecutor must testify to House