President Donald Trump, his family, and the Trump Organization sued Deutsche Bank and Capital One to prevent them from complying with congressional subpoenas.

The lawsuit alleges that the subpoenas "have no legitimate or lawful purpose" and were issued to "rummage through every aspect" of Trump's finances to "cause him political damage."

Deutsche Bank has a long-standing and controversial relationship with Trump and his businesses, and the bank is at the center of several congressional investigations into Trump's business dealings.

President Donald Trump, his children, the Trump Organization, and the Trump family trust filed a lawsuit Monday against Deutsche Bank and Capital One to bar them from complying with congressional subpoenas.

The suit, first reported by The New York Times, alleges that the subpoenas "have no legitimate or lawful purpose" and were issued to "harass" Trump and "to rummage through every aspect of his personal finances, his businesses, and the private information of the President and his family, and to ferret about for any material that might be used to cause him political damage."

Deutsche Bank informed Trump on April 17 that it had received Congress' subpoenas, which seek "records and/or information relating to banking activities, including information regarding accounts, financings, and related financial information" for the plaintiffs, the filing said. The bank was preparing to turn over the information to lawmakers by May 6.

The court filing said the congressional subpoena sought the records and financial information related to Trump's and his business' "parents, subsidiaries, affiliates, branches, divisions, partnerships, properties, groups, special purpose entities, joint ventures, predecessors, successors or any other entity in which they have or had a controlling interest."

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The subpoenas also extend to all "current or former employees, officers, directors, shareholders, partners, members, consultants, managers, senior associates, staff employees, independent contractors, agents, attorneys or other representatives."

The Trump legal filing said the subpoenas asked Deutsche for documents relating to those categories since January 1, 2010, though some documents had no time limit.

Deutsche Bank, which has a long and controversial history of doing business with the Trump family, is at the center of a joint investigation into Trump's finances by the House Financial Services Committee and the House Intelligence Committee.

Among other things, the bank drew scrutiny for being one of the only institutions willing to lend money to the Trump Organization in recent years.

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According to financial disclosures and public filings from 2012 to 2015, Deutsche has loaned Trump's businesses more than $300 million to finance a golf course in Florida and hotels in Chicago and Washington.

Jared Kushner, Trump's senior adviser and son-in-law, has also disclosed that he and his mother have shared an unsecured line of credit from the bank ranging from $5 million to $25 million.

When congressional investigators announced in January that they would zero in on Deutsche Bank, it said in a statement that it was "engaged in a productive dialogue with the House Financial Services and Intelligence Committees to determine the best way of assisting them in their official oversight functions," adding, "We remain committed to providing appropriate information."

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"We filed this case to protect the privacy rights of the President, his family and their businesses," Trump's lawyers said in a statement to The Times. They added that the subpoenas issued by the committees "are unlawful and illegitimate."

"They seek information going back decades from anyone with even a tangential connection to the President, including children, minors, and spouses," the statement continued. "Every citizen should be concerned about this sweeping, lawless, invasion of privacy. We look forward to vindicating our clients' rights in this matter."

Rep. Maxine Waters, the chairwoman of the House Financial Services Committee, and Rep. Adam Schiff, the chairman of the House Intelligence Committee, said in a joint statement that the lawsuit was "meritless" and demonstrated "the depths to which President Trump will go to obstruct Congress's constitutional oversight authority."

"This lawsuit is not designed to succeed; it is only designed to put off meaningful accountability as long as possible," the statement continued.

Deutsche Bank is also in the process of turning over documents about Trump's finances to the office of New York Attorney General Letitia James, a person familiar with the matter confirmed to INSIDER last week.

James in March subpoenaed Deutsche Bank and Investors Bank in New Jersey for records related to several Trump properties. James' subpoena was based on the testimony that Michael Cohen, Trump's former lawyer and longtime fixer, gave in February to the House Committee on Oversight and Reform.