High-Ranking, Career DOJ Antitrust Division Official Joins BakerHostetler

Since 2002, Ann O'Brien has been involved in virtually every major criminal enforcement and policy decision made by the division.

Press Releases / February 18, 2020

WASHINGTON and PHILADELPHIA – Feb. 18, 2020 – BakerHostetler announced today that Ann O’Brien, most recently assistant chief of the Competition Policy & Advocacy Section and special counsel for Criminal Policy at the U.S. Department of Justice (DOJ) Antitrust Division, has joined the firm as a partner in the firm’s Washington, D.C., and Philadelphia offices. O’Brien is the third recent notable addition to BakerHostetler’s Antitrust and Competition team, following Jeffrey Martino, former chief of the DOJ Antitrust Division’s New York office, and Marc Schildkraut, former assistant director with the Federal Trade Commission’s Bureau of Competition in Washington, D.C. O’Brien will also serve as part of the firm’s White Collar, Investigations and Securities Enforcement and Litigation team.

Over nearly two decades, O’Brien rose through the DOJ’s ranks to hold senior leadership and management positions. She served as a trial attorney, a special assistant to the civil and criminal directors of enforcement in the Office of Operations, the assistant chief of two sections, counsel to the assistant attorney general, senior counsel, and acting director of criminal enforcement. As acting director, O’Brien was the second-highest career official running the Antitrust Division’s criminal program, where she supervised more than 120 attorneys across five offices.

Most recently as assistant chief of the Competition Policy & Advocacy Section and special counsel for Criminal Policy, O’Brien was the leading authority on antitrust compliance programs and the application of U.S. Sentencing Guidelines to antitrust crimes, and she consulted on complex policy, charging, leniency and sentencing issues. With years of experience reviewing and assessing compliance programs, including helping draft the Antitrust Division’s recent compliance guidance, O’Brien is well qualified to counsel clients on what constitutes an effective antitrust compliance program and gold-standard antitrust training.

“Ann brings to our nationally recognized, diverse antitrust team extraordinary senior leadership experience at all levels of the DOJ Antitrust Division, including serving as the acting director of criminal enforcement managing the division’s cartel investigations and prosecutions internationally, and she was one of the top-ranking women in the division,” said Carl W. Hittinger, BakerHostetler’s Antitrust and Competition team leader.

“Given Ann’s wide-ranging and deep experience leading domestic and international white collar and antitrust investigations, she was the go-to person for attorneys in the DOJ Antitrust Division. Now that she is at BakerHostetler, corporate clients have the opportunity to avail themselves of her valuable counsel,” said George A. Stamboulidis, co-leader of BakerHostetler’s national White Collar, Investigations and Securities Enforcement and Litigation team. “We are thrilled to welcome her to the team.”

“As one of the longest-serving career prosecutors and policy authorities, with exceptional knowledge regarding the DOJ’s enforcement practices and policy decision-making processes, Ann will be a valuable resource for our clients – as an attorney comfortable in the courtroom as well as providing advice to navigate compliance and cartel investigation matters,” said W. Ray Whitman, chair of the firm’s national Litigation Practice Group.

“I truly value the nearly two decades I spent at the DOJ and am proud of my accomplishments during my tenure. I am excited by the opportunity to use my experience in complex antitrust and white collar investigations, negotiations, litigation and compliance among a team of fantastic people at BakerHostetler,” said O’Brien. “With companies often facing exposure in multiple jurisdictions and with numerous enforcers, my understanding of underlying regulatory and enforcement frameworks will help those who want to consolidate their matters at BakerHostetler – where we are able to handle all facets of the work.”

O’Brien received her B.A. from the University of Notre Dame and her J.D. from Northeastern University School of Law. She also served as a law clerk to Judge Deborah Robinson of the U.S. District Court for the District of Columbia.

BakerHostetler’s Litigation Practice Group consists of nearly 400 attorneys across the firm’s offices nationwide. With its roster of litigators that includes former prosecutors, veteran civil trial lawyers and former government enforcement officials, including nearly 20 lawyers formerly with the DOJ, the firm’s clients benefit from a team that can successfully represent them in nearly any type of case and proceeding. The Antitrust and Competition team includes more than 40 lawyers across the country and is recognized for thoughtful, practical strategies focused on positioning clients for success in the most crucial matters. Additionally, BakerHostetler is one of the few firms in the country that successfully defends large-scale class action antitrust matters, including taking those cases to trial and through appeal. The firm’s White Collar, Investigations and Securities Enforcement and Litigation team comprises some of the country’s most experienced and seasoned lawyers, many of whom have served as former federal and state prosecutors and Securities and Exchange Commission enforcement attorneys.


About BakerHostetler

Recognized as one of the top firms for client service, BakerHostetler is a leading law firm that helps clients around the world address their most complex and critical business and regulatory issues. With six core practice groups – Business, Digital Assets and Data Management, Intellectual Property, Labor and Employment, Litigation, and Tax – the firm has nearly 1,000 lawyers located coast to coast. For more information, visit bakerlaw.com.


Ivette Delgado, 202.861.1766 (idelgado@bakerlaw.com), or Gabi Valentine, 202.861.1582 (gvalentine@bakerlaw.com)