“Despite its mandatory obligation, the Treasury Department failed to comply with the law and denied the committee’s request,” committee chairman Richard Neal said in a press release.
In April the committee formally requested president Trump's personal tax returns from 2013 to 2018 from the Internal Revenue Service (IRS).
It then subpoenaed Treasury secretary Steven Mnuchin and IRS chief Charles Rettig. They defied the subpoenas, arguing that there was no legislative purpose for the request to disclose the documents.
In the suit filed today it says, “Defendants have now—for what the Committee believes is the first time ever— denied a Section 6103(f) request in order to shield president Trump’s tax return information from Congressional scrutiny. In refusing to comply with the statute, defendants have mounted an extraordinary attack on the authority of Congress to obtain information needed to conduct oversight of Treasury, the IRS, and the tax laws on behalf of the American people who participate in the nation’s voluntary tax system.”
A subpoena has also been served on the president’s son, Donald Trump Jr. President Trump has repeatedly rejected Democrat requests for his tax returns, and has sued Deutsche Bank, Capital One, and Mazars US to prevent their release.
A recent exposé by the New York Times showed that Trump’s core businesses operated at a massive loss between 1985-1994. In response, the president claimed that the $1bn (£795.8m) loss was deliberately calculated “for tax purposes”.