Marcus Christian is a Washington DC partner in Mayer Brown's Cybersecurity & Data Privacy practice and White Collar Defense & Compliance group. Since joining Mayer Brown in 2013, Marcus has represented clients in matters involving data security planning, board governance of cybersecurity, cyber fraud, data breach response, and congressional investigations, among others.

Previously, he was the executive assistant United States attorney at the US Attorney’s Office for the Southern District of Florida, the third-highest ranking position in one of America’s largest and busiest offices of federal prosecutors. In this role, Marcus worked on the senior management team with responsibility for the Criminal, Civil, Appellate, Asset Forfeiture and Administrative Divisions. Among other things, he oversaw a number of identity theft task forces, maintained critical incident response readiness, and supervised investigations and prosecutions of crimes related to data breaches. Marcus developed strong working relationships with members of the Federal Bureau of Investigation, the United States Secret Service, and other agencies that investigate computer and data crimes. He also held a top secret security clearance.

Prior to joining the US Attorney’s Office, Marcus was the chief of staff for US Representative Peter Deutsch of Florida’s 20th Congressional District. He joined the congressman after working for TSIC, Inc., a statewide nonprofit organization that provides full-tuition, four-year college scholarships to thousands of Florida's low-income students. At TSIC, Marcus served as chief operating officer and legal counsel and later as president.

Earlier in his career, Marcus was selected by the Attorney General’s Honors Program to work as an attorney in Appellate Section of the Tax Division of the United States Department of Justice in Washington DC. He also clerked for Judge H. Robert Mayer of the United States Court of Appeals for the Federal Circuit in Washington, DC.

Staying Ahead of the Curve: Cybersecurity and Data Privacy–Hot Topics for Global Businesses
Securities Investigations: Internal, Civil and Criminal


Yale Law School, JD

University of Oxford, MSc
Rhodes Scholar

Williams College, BA
Phi Beta Kappa



  • District of Columbia
  • Maryland


  • US Court of Appeals for the Fifth Circuit
  • US Court of Appeals for the Ninth Circuit
  • US Court of Appeals for the Tenth Circuit
  • US Court of Appeals for the Federal Circuit
  • US District Court for the District of Maryland
  • US District Court for the District of Columbia
  • US District Court for the Southern District of Illinois
  • US District Court for the Eastern District of Michigan


  • Member of Leadership Florida
  • 5000 Role Models of Excellence Project
  • Vice-chair of WLRN Public Radio & Television’s Community Advisory Board.  WLRN was winner of three national Edward R. Murrow Awards in 2013, including one for National Network Radio Investigative Reporting 
  • Named to Cybersecurity Docket's "Incident Response 30" in 2019, recognizing 30 of the "best and brightest data breach response lawyers in the business." The publication also noted that those recognized "have established themselves as the 'first call' for companies hit with a cyber attack or other data security incident." Marcus was also named to the list in 2018 and 2016.
  • Named to Washingtonian’s Top Lawyer list in 2018 and 2019.