(Bloomberg) -- Lawyers for Donald Trump are trying to convince a judge that the president can’t be investigated for a crime.

They’re trying to block the Manhattan District Attorney’s subpoena for Trump’s tax records. But while Trump could succeed in his challenge, legal experts said they don’t expect the judge to rule in a way that grants the sweeping degree of immunity from prosecutorial scrutiny that Trump is claiming for himself, his companies and the people around him.

“Trump’s lawyers are arguing that because he can’t be criminally charged, he can’t even be investigated,” said Jed Shugerman, a professor at Fordham University School of Law in New York. “The argument, to boil it down, is that a president is above the law.”

Manhattan District Attorney Cyrus Vance Jr. is probing whether the president’s company falsified business records related to hush-money payments to porn actress Stormy Daniels and former Playboy model Karen McDougal. Both women claim to have had sexual relationships with Trump.

Trump’s former personal lawyer, Michael Cohen, admitted to orchestrating hush payments to the women and released an audio recording in which he discusses a payment to McDougal with Trump. Cohen pleaded guilty last year to campaign-finance violations and is serving a three-year sentence.

Last month, a New York grand jury convened by Vance issued a subpoena to Mazars USA, Trump’s accountants, for years of tax records. While the Trump Organization turned over 3,376 pages of business records to the prosecutor, Trump has sued to block the subpoena to Mazars.

U.S. District Judge Victor Marrero in Manhattan has scheduled a hearing on Trump’s request for Wednesday. Late Tuesday, the Justice Department jumped in the fray on Trump’s behalf and asked the judge to temporarily block the subpoena while it decides whether to take part in the case.

‘Unfairly Targeting’

The president “cannot be subject to criminal investigation, for any conduct of any kind, while he is serving as president,” Trump’s lawyers said in court papers. They argued that Vance is unfairly targeting him for political reasons and that the case could infringe on his constitutional powers.

The lawsuit by Trump is part of his broader legal effort to shut down inquiries into his finances at a time when Democrats say they will initiate an impeachment inquiry and are preparing to take him on in the 2020 election. So far the president has had limited success in court, but has been able to use the legal process to delay the release of information.

In the suit against Vance, filed last week in Manhattan federal court, Trump claimed the subpoena to Mazars is unconstitutional and asked Marrero to declare it invalid.

The president’s lawyers want Vance to agree, or be required, to delay enforcement of the subpoena while its legality is decided in court. If unsuccessful, Trump’s lawyers said they will file emergency appeals with the federal court of appeals in New York or with the U.S. Supreme Court.

2000 Memo

Trump’s central argument is based on a Justice Department policy, reflected in a 2000 memo by the department’s Office of Legal Counsel, that says the president can’t be charged criminally while in office, on the grounds that it makes it difficult or impossible to carry out his constitutional duties. His team is trying to extend the proposition to shield his companies and prevent a third party, Mazars, from providing evidence.

No courts have ruled on the issue.

Trump, in seeking a preliminary injunction to block Vance from enforcing the Mazars subpoena, has to show that he faces “irreparable harm” if he doesn’t get it. He also has to demonstrate that he’ll probably win the legal argument that the subpoena can’t be enforced.

“There will be no way to unring the bell” once Mazars turns over the documents, Trump’s lawyers argued. Prosecutors will already have seen the president’s confidential material with no way to remedy the situation.

The Trump Organization already has turned over documents to Manhattan prosecutors in response to a separate subpoena, but balked at providing any tax documents, prosecutors said. The prosecutors then served a grand jury subpoena on Mazars for tax filings and financial statements for Trump and several of his companies from 2011 to the present.

‘Blanket Immunity’

Vance said the president is making an unprecedented claim for “blanket immunity” that would extend to his businesses, employees, third parties like Mazars, and his conduct before he entered the White House.

Trump’s position “is that none of this conduct, unrelated to the office of the president, can be investigated while the president remains in office,” the district attorney said. They also dismissed the notion that Vance is targeting Trump or anyone else.

“The question is not whether a state prosecutor can indict a sitting president,” Vance argued in court papers. “There is no threatened or pending state charge against a sitting president. Instead, the sole question is whether a third-party business entity should be required to produce records relating to business transactions that took place among a variety of individuals and entities -- including the president -- before the president took office.”

Vance disputed the the “irreparable harm” alleged by Trump’s lawyers, saying his office is required by law and legal ethics to keep the information confidential. If a court later agrees with Trump that Mazars shouldn’t have been required to turn over the tax filings, prosecutors could just destroy them or return them, he said.

Which Court?

In Wednesday’s hearing, Marrero may first question Trump’s team why the case is in federal court at all. Vance claims that if Trump has a valid challenge to the Mazars subpoena, “it should be litigated in the New York courts having jurisdiction over the grand jury that issued the subpoena.”

Prosecutors are asking Marrero to dismiss the case to allow Trump to pursue it in state court, just a few doors up the block from the federal courthouse in Manhattan. Trump’s side will argue that it should stay in federal court because the turns on constitutional considerations.

Separately, Trump is appealing orders by federal judges in New York and Washington that would allow committees controlled by House Democrats to obtain his records from Deutsche Bank AG, Capital One Financial Corp. and Mazars. Trump backers also are challenging a California requirement that presidential candidates release their tax returns in order to get placed on a primary ballot.

The case is Trump v. Vance, 19-cv-8694, U.S. District Court, Southern District of New York (Manhattan).

To contact the reporter on this story: Bob Van Voris in federal court in Manhattan at rvanvoris@bloomberg.net

To contact the editors responsible for this story: David Glovin at dglovin@bloomberg.net, Steve Stroth, Peter Blumberg

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