Washington (CNN) President Donald Trump is suing his long-time accounting firm Mazars USA and New York district attorney Cyrus Vance to attempt to stop his accounting records and tax returns from being sent to the local prosecutor, arguing he can't be prosecuted while in the White House.

The suit is the boldest broadside yet against any local or state prosecutors who may want to investigate Trump while he serves in the White House. For the first time, Trump's private legal team pushes an argument into federal court that the President should be immune from criminal investigation while in office.

"Virtually 'all legal commenters agree' that a sitting President of the United States is not 'subject to the criminal process' while he is in office," his attorneys write at the start of the complaint, citing a legal memo and a Yale Law Journal article. "Yet a county prosecutor in New York, for what appears to be the first time in our nation's history, is attempting to do just that."

Trump's lawsuit says Vance's actions are politically motivated to "harass" him and hurt the President during his reelection campaign, and it says Vance's subpoenas are unconstitutional because they're part of an attempt to investigate a sitting President.

Trump's team, however, acknowledges that "no court has had to squarely consider the question" of whether a sitting President can be criminally prosecuted or investigated.

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