Billionaire investor and Democratic activist Tom Steyer speaks to the Iowa Latino and Asian Coalition in January. (Charlie Neibergall/AP)

Billionaire Tom Steyer is launching a campaign to try to disbar Attorney General William P. Barr from practicing law, the latest Democratic attack on the nation’s top law enforcement officer following allegations that he lied to Congress about special counsel Robert S. Mueller III’s report.

Need to Impeach, a group pushing impeachment of President Trump, is planning to have Virginia-based supporters file complaints against Barr with the Virginia State Bar, for which the attorney general is a member. The group was announcing its plans on Friday.

Democrats, including House Speaker Nancy Pelosi (D-Calif.), have accused Barr of lying to Congress in early April when he suggested he did not k now why or whether Mueller’s team was unhappy with his four-page summery outlining top findings of the investigation into Russian interference in the 2016 election. At the time, however, Barr had received a late-March letter and phone call from Mueller saying he felt Barr’s summery did not “fully capture the context, nature and substance” of his probe.

“William Barr has forfeited his right to hold the office of the Attorney General,” Steyer, a longtime environmentalist and Democratic donor, said in a statement to The Washington Post. “Instead of upholding our laws and our tradition of democratic oversight, Mr. Barr has deliberately chosen to lie for a corrupt president who is acting more like a king than the leader of a free nation.”

He added: “Our system of justice depends on lawyers who accept their responsibility to uphold its ethical standards. Mr. Barr has proven incapable of or unwilling to do that, and he deserves to be disbarred.”

A Justice Department spokeswoman offered a one-word response when asked to comment for this story: “Ridiculous.” But the department generally has pushed back on any suggestion that Barr lied to Congress, calling those allegations irresponsible and inaccurate.

Additionally, Trump and top White House officials — who have been pleased with Barr’s handling of the Mueller situation and his testimony before the Senate this week — have instructed surrogates to go out and defend Barr as much as possible.

Steyer is unlikely to have success in his push, even as infuriated Democratic lawmakers might applaud and take up the call. Activists occasionally seek the disbarment of current or former government lawyers whose decisions they dislike, including lawyers who were involved in legal work surrounding the harsh treatment of terror suspects during the George W. Bush administration.

They are rarely successful — unless those officials are convicted of a crime. Trump’s former attorney Michael Cohen was disbarred after he pled guilty to felony charges. Former White House counsel John Dean was also disbarred after his guilty plea for his role in covering up the Watergate break-in.

The Steyer effort comes as multiple Democrats have called on Barr to resign and even floated impeachment of the attorney general. House Judiciary Committee Democrats, at the very least, plan to move to hold Barr in contempt as early as next week.

House Democrats’ anger with Barr extends beyond his handling of the four-page summary, however. Barr has now ignored two subpoenas from House Democrats or instructed his subordinates to do so: a Judiciary panel demand that he turn over the full, unredacted Mueller report as well as a summons to depose a Justice Department official involved in the 2020 Census.

On Friday, House Judiciary Committee Chairman Jerrold Nadler (D-N.Y.) gave Barr yet another deadline for the full Mueller document. If he does not receive it by Monday, House Democrats will move to issue a contempt citation against Barr and take him to civil court to try to persuade a judge to force the full release of Mueller’s findings.

Devlin Barrett contributed to this report.