President Donald Trump’s longtime personal attorney is the subject of a complaint filed by a watchdog group Thursday with the disciplinary body in charge of Washington attorneys, allegedly for dispensing legal advice to unrepresented White House staffers, a violation of bar rules and legal ethics.

Campaign for Accountability, a government ethics watchdog organization, filed the complaint with the District of Columbia Court of Appeals' Office of Disciplinary Counsel in response to a story in Sunday’s New York Times that said Marc Kasowitz, who has represented Trump for 15 years, told presidential aides they did not yet need to hire lawyers in response to special counsel Robert Mueller’s Russia investigation.

Read: Who Is Marc Kasowitz? Trump Defended By Personal Lawyer Following Comey Hearing

By telling White House aides they did not need to hire lawyers, Kasowitz dispensed legal advice to people who not only weren’t his clients, but whose interests in the coming legal storm might be contrary to the president’s, the complaint alleges. The complaint, which asks the office to open an investigation, comes as Mueller’s investigation reportedly has expanded to examine whether the president attempted to obstruct justice.

Robert Mueller Special Counsel Robert Mueller is going to launch an investigation on President Donald Trump. In this photo, Mueller testifies during a hearing before the House Judiciary Committee on Capitol Hill in Washington, July 26, 2007. Photo: Getty Images/Alex Wong

“It was really concerning to read he was providing legal advice to White House staffers,” Daniel Stevens, executive director of the Campaign for Accountability, told International Business Times. Stevens is an alumnus of Citizens for Responsibility and Ethics In Washington, the watchdog group that filed suit against the president just days after his inauguration over his foreign business dealings.

“They weren’t his clients and they might take heed of that advice and it might not be in their best interest. [Kasowitz] needs to be held accountable for giving that advice,” Stevens said.

The D.C. bar, as well as the American Bar Association’s model rules, which have been adopted by all 50 states and the District of Columbia, forbid attorneys from giving legal advice to people who don’t have lawyers, other than recommending they retain counsel, if the “interests of such person are or have a reasonable possibility of being in conflict with the interests of the lawyer’s client.”

Kasowitz’s discussions with White House staff reportedly bypassed White House counsel Donald F. McGahn II,  a departure from previous protocol that worried former attorneys who have held that position.

"The president’s private lawyer is representing only his interests, not the interests of the United States government or the individual interests of the White House staff,” Robert F. Bauer, who was White House counsel under President Barack Obama, told the Times.

The White House declined to comment and directed IBT to send questions to Kasowitz, who did not respond to IBT’s inquiries. A spokesperson for Kasowitz previously said the Times’ categorization of the meeting was “inaccurate,” but, according to the Times, “would not specify how.”

Read: Trump Calls Comey A 'Leaker,' Says He Is Open To Testifying Under Oath Against Him

Campaign for Accountability copied the complaint to the New York State Bar. Court records indicate Kasowitz is not a member of the D.C. Bar but is a member of the New York Bar. The committees in D.C. and New York that evaluate complaints would not confirm they received the complaint, as complaints against attorneys are confidential unless a complaint ends in disciplinary action, which can run the gamut from requiring attorneys take continuing education classes to disbarment. 

The Committee on Character and Fitness for Manhattan and the Bronx, which has jurisdiction over Kasowitz's law practice, told IBT that Kasowitz has never been disciplined by the courts for misconduct since becoming a member of the New York Bar in 1978.

Trump hired Kasowitz to represent him in all matters connected to the Russian investigation at the end of May, shortly after the Justice Department tapped Mueller as special counsel.

After FBI Director James Comey testified to a Senate panel June 7 about his interactions with Trump, Kasowitz attacked Comey and defended Trump at the press.

“From before this president took office to this day, it is overwhelmingly clear that there have been and continue to be those in government who are actively attempting to undermine this administration with selective and illegal leaks of classified information and privileged communications,” Kasowitz said. “Mr. Comey has now admitted that he is one of these leakers.”

Trump’s legal team has said it is planning on filing a complaint against Comey for leaking conversations with the president. The team initially planned to file the complaint this week, but the legal team’s spokesperson confirmed on Tuesday the complaint would most likely be filed next week. It’s unclear with which office in the Justice Department, which oversees the FBI, the legal team will file the complaint.

Kasowitz has represented Trump in a variety of matters since the turn of the century, including defending the president in the Trump University lawsuit, keeping the president’s divorce records sealed, restructuring Trump casino bondholder debt and suing a Trump biographer in 2009 for citing unnamed sources claiming the real estate mogul wasn’t actually a billionaire.

ProPublica has reported Kasowitz bragged to friends about convincing Trump to fire Manhattan U.S. Attorney Preet Brahara, who was investigating Tom Price, Trump's secretary of health and human services, at the time of his firing. 

Kasowitz’s firm, Kasowitz Benson Torres LLP, employs former Connecticut Sen. Joseph Lieberman, whom  Trump briefly considered for FBI director after he fired Comey. Trump tapped Kasowitz’s partner, David Friedman, to serve as ambassador to Israel prompting the firm to change its name  (until late March, Kasowitz’s firm’s name was Kasowitz Benson Torres & Friedman). In addition to Trump, Kasowitz also represents Russia’s largest bank, Sberbank, which counts the Russian government as a majority shareholder.

Vice President Mike Pence has also retained counsel to represent him in the Russia inquiry, the Washington Post reported Thursday. Pence hired Richard Cullen, a former U.S. attorney in the Eastern District of Virginia, a Pence spokesman confirmed to the Post.