Deputy solicitor general Michael Dreeben
Deputy solicitor general Michael Dreeben (Photo: Diego M. Radzinschi / NLJ)

Special counsel Robert Mueller III has recruited the Justice Department’s top criminal law expert to help with his investigation of ties between the Trump presidential campaign and Russian officials.

Deputy solicitor general Michael Dreeben, who has argued more than 100 cases before the U.S. Supreme Court and oversees the Justice Department’s criminal appellate docket, will be assisting Mueller on a part-time basis, according to sources familiar with the arrangement.

While helping Mueller, Dreeben will continue in his role in the solicitor general’s office, with other lawyers in the office pitching in to help him with upcoming criminal cases.

The move signals that Mueller is seeking advice on the complexities that have arisen already in the investigations, including what constitutes obstruction of justice.

“Michael Dreeben is to criminal law what Robert Mueller is to investigations,” former acting Solicitor General Neal Katyal said Thursday night. “Literally the very best. Yet another sign of how serious Mueller is about this matter.” Now a partner at Hogan Lovells, Katyal has been a key figure in challenging President Donald Trump’s travel ban.

In 2005, Dreeben argued and lost a case for the government involving obstruction-of-justice charges against the Arthur Andersen accounting firm in the wake of the Enron scandal.

At an event marking Dreeben’s 100th Supreme Court argument in 2016, justices praised his expertise in the area of criminal law. He argued his first case at the court in 1989 against John Roberts Jr., then in private practice, and has worked in the solicitor general’s office under Republicans and Democrats ever since.

Justice Elena Kagan, who worked with Dreeben as solicitor general before joining the high court, said she felt honored “in the company of a magnificent attorney doing a magnificent job.”

Justice Ruth Bader Ginsburg said that when Dreeben approaches the lectern at the Supreme Court, “I know he will tell it straight.”