WASHINGTON — Former President Donald Trump and attorney Rudy Giuliani are being accused of conspiring with the far-right groups Proud Boys and Oath Keepers to incite the Jan. 6 insurrection in a civil lawsuit filed on Tuesday in federal court by the Democratic chairman of the House Homeland Security Committee. The suit cites a post-Civil War law designed to combat violence and intimidation by the Ku Klux Klan.

The lawsuit, filed by Mississippi Democratic Rep. Bennie Thompson in his personal capacity, is the first civil action filed against the former president related to the attack at the US Capitol and comes days after the Senate acquitted Trump in his impeachment trial.

If it proceeds, it would mean the former president and others would be subject to discovery and depositions, potentially exposing details and evidence that weren't released during the Senate impeachment trial.

Thompson points to Trump's words and tweets in the months leading up to the insurrection to accuse Trump and Giuliani of mobilizing and preparing their supporters for an attack to prevent Congress from certifying the 2020 election results on Jan. 6.

The lawsuit cites a scarcely used federal statute passed after the Civil War that was intended to combat violence from the Ku Klux Klan; it allows civil actions to be brought against people who use "force, intimidation, or threat" to prevent anyone from upholding the duties of their office.

The National Association for the Advancement of Colored People (NAACP), a civil rights organization in the US, is backing the lawsuit and helping to represent Thompson in court.

"As part of this unified plan to prevent the counting of Electoral College votes," the lawsuit states: "Defendants Proud Boys and Oath Keepers, through their leadership, acted in concert to spearhead the assault on the Capitol while the angry mob that Defendants Trump and Giuliani incited descended on the Capitol."

"The carefully orchestrated series of events that unfolded at the Save America rally and the storming of the Capitol was no accident or coincidence. It was the intended and foreseeable culmination of a carefully coordinated campaign to interfere with the legal process required to confirm the tally of votes cast in the Electoral College."

The former president and many Republicans argued the impeachment trial was unconstitutional because he is no longer in office. As such, Thompson notes Senate Minority Leader Mitch McConnell's speech Saturday where the Kentucky Republican seemed to encourage litigation against Trump.

"We have a criminal justice system in this country. We have civil litigation," McConnell said after voting to acquit Trump. "And former presidents are not immune from being accountable by either one."

Jason Miller, a spokesman for Trump, said the former president did not incite or work to incite riots at the Capitol.

"President Trump has been acquitted in the Democrats' latest Impeachment Witch Hunt, and the facts are irrefutable," Miller said in a statement. "President Trump did not plan, produce or organize the Jan. 6th rally on the Ellipse. President Trump did not incite or conspire to incite any violence at the Capitol on Jan. 6th."

Giuliani did not immediately respond to a request for comment. — Courtesy CNN