"This lawsuit arises out of Attorney General Barr’s and Secretary Ross’s unlawful refusals to comply with duly authorized, issued and served [Oversight] Committee subpoenas," the lawsuit filed in US District Court for the District of Columbia said.
Cabinet officials, which are nominated by the president and confirmed by the US Senate, are generally required to testify when called on by Congress, however, President Donald Trump refuses to cooperate with what he calls a bogus impeachment probe and has prevented officials in his administration from cooperating.
The lawsuit cites Article I of the US Constitution, which gives Congress oversight of the executive branch and a prior Supreme Court ruling that upholds the congressional "power of inquiry - with process to enforce it."
House of Representatives Intelligence Committee Chairman Adam Schiff has said the impeachment inquiry will go forward regardless of any pending litigation. Lawmakers have said they hope to conclude the inquiry before the New Year.
With appeals to higher courts, lawsuits often take years to conclude.
The Oversight Committee is one of six committees in the House of Representatives - including the Intelligence Committee - seeking evidence for lawmakers who are eager to impeach the president.
