Dietrich L. Snell is a partner in the Litigation Department and co-chair of the White Collar Defense & Investigations Group. Dieter has extensive experience in law enforcement-related matters spanning a wide range of disciplines. He has both federal and state level prosecutorial and investigative experience, having served for nearly two decades as an Assistant U.S. Attorney; as New York Deputy Attorney General; and as Senior Counsel to the National Commission on Terrorist Attacks Upon the United States (the 9/11 Commission).
Clients and Areas of Concentration
Dieter’s clients include corporations and senior executives involved in civil and criminal investigations and prosecutions performed by federal and state law enforcement and regulatory authorities, in such diverse areas as
He frequently handles sensitive internal investigations for corporate clients and other entities. Dieter’s practice also includes commercial litigation in both federal and state court.
Prosecutorial Experience
As the New York Deputy Attorney General, Dieter was responsible for the investigation, litigation and regulatory activities performed by the Division of Public Advocacy under former Attorney General Eliot Spitzer. He supervised approximately 300 professional staff and oversaw complex cases and investigations involving:
Before joining the New York Attorney General’s office, Dieter served for 11 years as Assistant U.S. Attorney for the Southern District of New York, notably handling the successful prosecution of 1993 World Trade Center bomber Ramzi Yousef for Yousef’s role in the 1994-95 plot to destroy 12 passenger jets in midair, as well as cases involving securities and commodities, bank and computer fraud, narcotics, money laundering, and racketeering offenses. As Deputy Chief Appellate Attorney, he supervised the preparation and submission of briefs to the U.S. Court of Appeals for the Second Circuit.
The 9/11 Commission
In his role as Senior Counsel to the 9/11 Commission, Dieter led the team assigned to investigate the plot that culminated in the September 11 attacks. He negotiated with the law enforcement, intelligence and diplomatic communities regarding access to documents, evidence, and witnesses; reviewed voluminous classified and unclassified materials; conducted witness interviews; advised commission members and assisted them at public hearings; and drafted and edited substantial portions of The 9/11 Commission Report.
New York City Bar – Co-Vice Chair, Committee on the Judiciary
Chambers USA: New York: Litigation: White-Collar Crime & Government Investigations 2013-2024
The Legal 500 United States: Litigation: White Collar Criminal Defense 2012-2023
The Legal 500 United States: Corporate Investigation & White-Collar Criminal Defense, 2024
Best Lawyers in America 2013-2025
New York Super Lawyers 2012-2022