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Mark J. Biros, a partner, co-founded the White Collar Defense & Investigations Group. He has over 35 years of investigative and trial experience as a legislative counsel, former prosecutor and as defense counsel, his current role.

On the federal level, Mark served as an Assistant U.S. Attorney for the District of Columbia from 1977 through 1988 and has tried over 100 jury trials. He also served as Deputy Chief of the Felony Trial Division. As a member of the Special Prosecutions Unit, Mark concentrated on complex federal criminal investigations. His investigative experience began as an Assistant Counsel to the U.S. Senate Committee on Presidential Campaign Activities, known informally as the “Watergate Committee.” His international practice has taken him to the United Kingdom, Germany, Italy, Belgium, Ireland, Mexico and Argentina, while focusing upon activities in Europe, the Middle East, South America, the Far East and Africa.

On the state level, he investigated and prosecuted political and police corruption in Philadelphia, Pennsylvania, where he was an Assistant Attorney General for several years.

In private practice, Mark has conducted internal investigations in defense of government allegations of violations of the Foreign Corrupt Practices Act, domestic and foreign tax laws, money laundering provisions, bribery, insider trading, anti-trust laws, and government contract fraud, as well as U.S. Customs and environmental law violations. He has helped clients identify internal control issues and establish procedures for compliance under Sarbanes-Oxley, SEC and other regulatory provisions, and has represented organizations and individuals that were the subject of congressional inquiries.

An adjunct Professor at Georgetown University Law Center for 30 years, Mark presently teaches Advanced Criminal Procedure. He has lectured on criminal law issues at the Federal Judicial Center, where the attendees were federal judges, and to Bar Associations and meetings of private and government attorneys. Further, he provides the firm’s clients with training on how to conduct internal corporate investigations. 

In 2015 Mark was appointed to serve as the Co-Chair of the Criminal Law Committee of the International Bar Association. He has been actively involved in the Committee’s efforts over the years. In 2014, he co-chaired a panel at the IBA’s Transnational Crime Conference in Istanbul on The International Whistleblower – Hero or Villain?  During 2013 - 2014, he was the Vice-Chair of the Committee. In 2012, he was selected to be a member of a panel at the IBA’s annual meeting in Dublin addressing the topic Navigating the Criminal Law Minefield: A Cautionary Tale for Defense Lawyers and Lawyers Representing Corporations.  During 2011 – 2012, Mark served as the Committee’s North American Regional Representative.  At the Transnational Crime Conference in June 2009, Mark gave a presentation on how to respond to, and manage, a coordinated multi-national law enforcement investigation. And in June 2008, Mark addressed the IBA’s Transnational Crime Conference in London on investigations of, and prosecutions for, violations of U.S. economic sanctions.  He also spoke at the Association’s 2008 annual meeting in Buenos Aires on Minimizing the Impact of Corruption on the Rule of Law & International Business - Detecting, Investigating & Responding to Corrupt Conduct.

Mark is a contributing author to two books: Corporate Counsel's Guide to Handling Government Investigations, and Business & Legal Guide to Online Internet Law. Additionally, he has written numerous articles for a variety of publications, including in-depth articles on internal investigations and white collar crime, which have appeared in the American Criminal Law ReviewNational Law Journal, Legal Times and Metropolitan Corporate Counsel publications.