The American Civil Liberties Union (ACLU) filed an ethics complaint against Attorney General Jeff Sessions late Thursday, asking the Alabama State Bar to investigate a potential rules violation after the former senator was revealed to have lied to Congress during his confirmation testimony.

"False testimony made under oath is one of the most serious ethical offenses a lawyer can make and one any state bar should investigate vigorously," said ACLU national political director Faiz Shakir. "Alabamians and Americans from all walks of life should be assured that the organizations responsible for regulating lawyers in their state take ethical violations seriously—no matter how powerful that lawyer may be."

Sessions has been a member of the Alabama State Bar since 1973. The legal association states that engaging in behavior "involving dishonesty, fraud, deceit, or misrepresentation" counts as professional misconduct, the ACLU noted in its complaint.

The civil rights group urged the bar to investigate and "take any appropriate disciplinary actions" against the attorney general and former Alabama lawmaker. The move came on the same day that Boston-based attorney J. Whitfield Larrabee filed a similar ethics complaint against Sessions, arguing that he had engaged in "unethical and criminal conduct" during his confirmation hearing.

Sessions testified before the Senate Judiciary Committee last month that he had not communicated with the Russian government during President Donald Trump's election campaign, but the Washington Post and other outlets have since revealed that he had contacted Russian Ambassador Sergey Kislyak at least three times.

The damning revelations have prompted widespread demands for Sessions to resign, which he has thus far ignored, despite recusing himself from any potential investigation into Russia's alleged involvement in the 2016 election.

"Few events are more corrosive to a democracy than having the Attorney General make false statements under oath about a matter the Justice Department is investigating," Christopher Anders, deputy director  of the ACLU's legislative office, said Thursday. "Jeff Sessions told a falsehood to the Senate, and did nothing to correct his statement until he was exposed by the press more than a month later. No attorney, whether just starting out as a new lawyer or serving as the country's top law enforcement officer, should lie under oath. The Alabama bar must investigate this wrong fully and fairly."