As a partner and co-chair of Covington's White Collar Defense and Investigations practice group, Aaron Lewis represents businesses, boards of directors, and individuals in sensitive, high-stakes government investigations, internal investigations, and regulatory enforcement matters.

He has advised clients facing alleged criminal and civil violations of the False Claims Act (FCA) and the Foreign Corrupt Practices Act (FCPA), as well as allegations of public corruption, export controls violations, obstruction of justice, and espionage. Aaron's clients have included companies and independent board committees in the aerospace and defense, automotive, technology, entertainment, and retail industries and he routinely leads internal investigations of alleged misconduct or compliance failures, including several investigations involving allegations of ineffective internal controls and dysfunctional workplace cultures. He returned to Covington in 2015 after six years of service in the Department of Justice (DOJ), first as Counsel to Attorney General Eric Holder in Washington, and later as an Assistant United States Attorney in Los Angeles.

During his service in the Justice Department, Aaron advised the Attorney General on a range of enforcement issues, including intellectual property protections, national security matters and civil rights. He worked closely with senior officials at the White House, the Justice Department, and several law enforcement agencies, including the FBI and DHS. As an Assistant United States Attorney, most recently in the National Security Section, Aaron investigated and prosecuted cases involving thefts of trade secrets, export control violations, and computer network intrusions. He also prosecuted cases involving bank fraud, false statements, and mail fraud. An experienced trial and appellate lawyer, Aaron has tried several cases to verdict, and argued before the Ninth Circuit Court of Appeals.