Jan is an accomplished investigations and trial lawyer with a national and international practice. He represents individuals and companies, both foreign and domestic, in regulatory and white collar criminal investigations and prosecutions. Jan coordinates cross-border investigations with civil, criminal and regulatory proceedings and handles complex civil litigation, civil enforcement actions and corporate internal investigations.

An experienced trial lawyer, Jan has tried well over 100 jury trials and numerous bench trials to verdict in U.S. federal and state courts. He is nationally and internationally recognized as an authority on financial fraud, transnational crime and regulatory offenses. These include civil and criminal securities fraud, tax fraud, bank fraud and money laundering, cybercrime and cryptocurrency trading, environmental crimes, public corruption and bribery offenses under the U.S Foreign Corrupt Practices Act (FCPA) and UK Bribery Act. Jan is one of only a handful of US lawyers to have successfully defended corporate and individual defendants in a major FCPA prosecution, United States v. Lindsey Manufacturing Company, et al.

As a federal prosecutor in the U.S. Department of Justice, Jan served in the Fraud and Special Prosecutions Section of the United States Attorney's Office in Los Angeles. As an Assistant U.S. Attorney, he conducted grand jury investigations and prosecuted federal fraud cases at trial and on appeal.

Jan is a past National Chair of the American Bar Association's National White Collar Crime Committee. He also served as Co-Chair of the International Bar Association's Business Crime Committee, helping to organize and present its annual Transnational Crime Conference in Istanbul, São Paulo and Panama, and mock trials in Dublin, Vienna and Washington, DC.

Jan has been recognized for his accomplishments in numerous national and international publications. He has been honored by his peers in all 32 editions of Best Lawyers in America, through 2026 Handzlik & Associates has again been recognized in the 2026 edition of Best Law Firms. Jan received the California Attorney of the Year Award from California Lawyer Magazine. He was named one of the “Top 100 Lawyers in California” by The Daily Journal and honored with the National Association of Criminal Defense Lawyers White-Collar Criminal Defense Award. Lexology Index has again recognized Jan as a Global Thought Leader in Business Crime Defense and Investigations.