David A. O’Neil, Partner, Debevoise & Plimpton LLP

David A. O’Neil is a litigation partner and member of the firm’s White Collar & Regulatory Defense Group. Recommended by Legal 500 US (2018), his practice focuses on white collar criminal defense, internal investigations, privacy and cybersecurity, congressional investigations and AML/sanctions enforcement defense. In 2018, Mr. O’Neil was recognized as a “Litigation Trailblazer” by the National Law Journal and a “White Collar MVP” by Law 360. He is also recognized by Chambers USA and Legal 500 (2018) as a leading lawyer in White-Collar Crime & Government Investigations.

Mr. O’Neil has a unique practice focused on representing clients in high-stakes matters involving significant legal, political and public relations implications. His experience spans criminal investigations by the U.S. Department of Justice and foreign law enforcement bodies, sensitive, confidential internal investigations for high-profile companies, investigations by the United States Congress, litigation brought by state Attorneys General and class action lawsuits.

Select representations include:

• Keppel Offshore & Marine Ltd.in an extensive internal investigation of the company’s work in the United States, Brazil, Singapore, Ukraine, Kazakhstan, and Azerbaijan. At the conclusion of the investigation, the Debevoise team, co-led by Mr. O’Neil, negotiated coordinated resolutions with the U.S., Brazilian and Singaporean criminal authorities in relation to corrupt payments to Petrobras and other Brazilian officials.
• Deutsche Bankin connection with ongoing investigations by the Department of Justice and other government authorities into various issues related to certain current government officials, associated individuals, and related entities.
• Ewart Brown, former Prime Minster of Bermuda,in a long-running investigation into allegations of fraud and corruption.
• The owners of the largest construction company in South Americain response to the U.S. criminal investigation of bribery related to the Lava Jato matter in Brazil.
• Twitter Inc.,in Department of Justice and Congressional investigations into Russian interference in the 2016 presidential election.
• Sally Yates, the former U.S. Deputy Attorney General and Acting Attorney General,in Congressional investigations related to Russian interference in the 2016 presidential election.
• Tim Mayopoulos, former CEO of Fannie Mae,in a hearing before the House Financial Services Committee.
• Michael Pearson, former CEO of Valeant Pharmaceuticals,in Congressional investigations related to the company’s restatement and sales practices.
• Apple Inc. and its former General Counsel Bruce Sewellin litigation involving encrypted data on a mobile device and related testimony before the House Judiciary Committee and the House Energy and Commerce Committee.
• FanDuel Inc.in defending Attorney General actions seeking to prohibit fantasy sports contests as illegal gambling, in defending and settling a lawsuit by the New York State Attorney General over allegations of false advertising, and in an internal investigation of the company’s internal controls, standards, and practices.

Prior to joining Debevoise in January 2015, Mr. O’Neil served for eight years in prominent positions within the Department of Justice. In early 2014, the President and Attorney General designated Mr. O’Neil to lead the Criminal Division, where he was responsible for supervising more than 600 attorneys investigating and prosecuting the full range of federal crimes, including corporate malfeasance, cybercrime, fraud offenses and money laundering. Mr. O’Neil also served as Deputy Assistant Attorney General for the Fraud Section. In that capacity, he supervised more than 100 prosecutors engaged in nationwide enforcement against FCPA violations, healthcare fraud, and securities and financial fraud.

Before moving to the Criminal Division, Mr. O’Neil served for three years as Senior Associate Deputy Attorney General and Chief of Staff to the Deputy Attorney General, the Department’s second-in-command. In that role, he was part of DOJ’s core management team with direct supervisory responsibility for more than two dozen attorneys. He participated in a broad range of high-profile matters, including significant FCPA prosecutions, the LIBOR investigations, and high-profile investigations of financial institutions for money laundering and Bank Secrecy Act violations.

Mr. O’Neil oversaw the DOJ’s response to multiple congressional investigations and brokered a landmark agreement with major technology companies over disclosures of government demands for customer information. In addition, Mr. O’Neil participated in negotiations with the Swiss government over the framework of Swiss cooperation in what eventually became the DOJ tax program.

In 2009, Mr. O’Neil served as Assistant to the Solicitor General. He argued three cases in the U.S. Supreme Court, authored more than 50 briefs filed with the Supreme Court, and handled appeals from high-profile white-collar criminal convictions.

Mr. O’Neil began his career at DOJ as a federal prosecutor in the U.S. Attorney’s Office for the Southern District of New York. As an Assistant U.S. Attorney, he tried numerous cases to successful jury verdicts and argued several appeals. He worked on multiple cases involving financial institutions, including bank fraud, mortgage and identity-theft matters.

Mr. O’Neil’s recent publications include “Staying A Step Ahead,” International Financial Law Review (July, 2015); “Enforcement Scrutiny Falling On Individuals,” The National Law Journal(May, 2015); and “New York State Department Of Financial Services Expands Its Cyber Focus To Insurers,” FC&S Legal (April, 2015).

Mr. O’Neil earned his J.D., magna cum laude, in 2000 from Harvard Law School, where he was an editor of the Harvard Law Review. He graduated magna cum laude from Princeton University, with a B.A. in 1995.

Upon graduation from law school, he clerked for two years, first for Judge Robert D. Sack of the U.S. Court of Appeals for the Second Circuit and then for U.S. Supreme Court Justice Ruth Bader Ginsburg.