Edward C. O’Callaghan’s distinguished career in senior government roles and significant private practice experience position him to successfully advise and defend public companies, global financial institutions, asset management firms and executives in international and domestic regulatory investigations, criminal prosecutions and congressional inquiries, including matters involving securities fraud, insider trading and market manipulation, bank fraud, money laundering, accounting fraud, criminal antitrust, healthcare fraud, US export controls and sanctions regimes, corruption, RICO, and FCPA.  

Mr. O’Callaghan joined the firm in 2020 after serving as DOJ’s principal associate deputy attorney general where he acted as the principal counselor to the department’s second highest official, the deputy attorney general, and a key advisor to the Attorney General. In that role, Mr. O’Callaghan helped manage 113,000 attorneys, agents, investigators, and administrators, 93 US attorney offices, and all DOJ law enforcement agencies such as the Federal Bureau of Investigation; Drug Enforcement Agency; Bureau of Alcohol, Tobacco and Firearms; US Marshals Service; and the Bureau of Prisons. He also worked regularly with various committees, leadership members and staffers in both chambers of Congress. He supervised the DOJ’s responses to constant Hill inquiries, including daily negotiations with committee leadership and staffers, and the preparation of DOJ leadership for hearings and briefings before Senate Judiciary, Senate Finance, Senate Permanent Select Committee on Intelligence, Senate Committee on Homeland Security and Government Affairs, the “Gang of Eight,” House Judiciary, House Oversight and Government Reform, and House Permanent Select Committee on Intelligence.

During his most recent DOJ tenure from November 2017 to December 2019, Mr. O’Callaghan also served as acting deputy attorney general, the principal deputy assistant attorney general in DOJ’s National Security Division and the acting assistant attorney general in charge of the National Security Division. In this latter role, Mr. O’Callaghan supervised all units and components within the NSD, including the Counterterrorism Section, Counterintelligence and Export Control Section, Office of Intelligence, Office of Law & Policy, Foreign Investment Review Staff, and Office of Justice for the Victims of Overseas Terrorism.

Mr. O’Callaghan was a partner in two international law firms from 2009 to November 2017, during which his practice focused on representing financial institutions, public companies, asset management firms and executives in an array of international and domestic regulatory investigations and criminal prosecutions.

From 1998 until 2008, Mr. O’Callaghan was an Assistant US Attorney for the Southern District of New York and Co-Chief of the Terrorism & National Security Unit during the last three years of his tenure.


  • Fokker Services, B.V., in the successful negotiation of a Deferred Prosecution Agreement with DOJ, US Treasury (OFAC) and Commerce Dept (BIS), involving historical violations of the US sanctions, and related landmark court proceedings in US District Court for the District of Columbia and the US Court of Appeals for the DC Circuit. 
  • Achilles Macris, the former head of the London branch of JP Morgan’s chief investment office, where the trader nicknamed the "London Whale," Bruno Iksil, worked, in the DOJ, SEC, CFTC, Federal Reserve, FCA and congressional investigations into a reported $6 billion trading loss.
  • Jeffrey Webb, the former President of CONCACAF and FIFA Executive Committee Member, in the criminal Racketeer Influenced and Corrupt Organizations Act (RICO) indictment in the US District Court for the Eastern District of New York.
  • Global depositary bank and individual officers and employees in a SEC Enforcement investigation involving the trading and pricing practices of depository banks in the pre-release American Depositary Receipts market.
  • Global investment bank and individual officers and employees in SEC, DOJ and State Attorneys General investigations related to RMBS structuring and trading practices, and separate SEC inquiries related to internal investment bank policies and procedures.
  • Global financial institution employees in DOJ and CFTC investigations related to certain trading activity by the bank’s New York “Swaps Desk” involving trading ahead of, or “pre-hedging,” block futures trades with its counterparties.
  • Global financial institution in several SEC enforcement investigations of trading practices and criminal tax investigations in United States and European Union.
  • Global financial institution employees in DOJ/IRS investigation into bank’s private wealth customers’ US tax compliance policies.
  • Global financial institution in DOJ, SEC, and Federal Reserve investigations into possible FCPA violations related to 2008 financial crisis loan solicitation and structuring.
  • Global financial institution in DOJ, CFTC and FSA LIBOR and related rates investigations.
  • Big 4 accounting firm in an SEC Enforcement investigation of client’s financial statement filings.


  • Mr. O’Callaghan is a recipient of the Edmund Randolph Award, the highest award given to a civilian by the Department of Justice, and the Attorney General’s medallion, both of which were presented to him by the Attorney General in 2020. He also received the US Attorney General’s Award for Distinguished Service (2008), and the Director’s Award for Superior Performance as an Assistant US Attorney (2000).
  • In Chambers 2016, Mr. O’Callaghan was recommended by clients for his extensive white-collar practice, with interviewees highlighting his “substantive experience in the sanctions area,” “very strong advocacy skills” and “excellent judgment.”
  • Selected by peers for inclusion in Best Lawyers in America for white-collar criminal defense (2013–2024).

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  • Education

    • JD, New York University School of Law, 1994

    • BA, Government, Georgetown University, 1991

      magna cum laude Phi Beta Kappa
  • Clerkships

    • The Hon. Kevin Thomas Duffy, US District Court for the Southern District of New York, 1995 - 1996

  • Government Experience

    • Department of Justice

      National Security Division

      Principal Deputy Assistant Attorney General, Acting Assistant Attorney General
    • Department of Justice

      Office of the Deputy Attorney General

      Principal Associate Deputy Attorney General, Acting Deputy Attorney General
    • Department of Justice

      United States Attorney's Office

      Co-Chief, Criminal Division - Terrorism and National Security Unit, Southern District of New York
    • Department of Justice

      United States Attorney's Office

      Assistant US Attorney, Southern District of New York

* Not admitted in the District of Columbia. Practice supervised by members of the firm who are members of the District of Columbia Bar.


* Not admitted in the District of Columbia. Practice supervised by members of the firm who are members of the District of Columbia Bar.


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