Overview
John Mucciolo focuses his practice on commercial litigation, white-collar criminal defense, and internal and government investigations. He has experience handling cases from pre-litigation investigation through trial and appeals.
John has authored briefs on numerous substantive legal and procedural issues and has drafted pleadings, discovery devices, and responses. He has managed all aspects of e-discovery and has counseled clients in preparation for interviews with government regulators and prosecutors.
John maintains an active pro bono docket, with a special interest in criminal justice and environmental issues.
- New York
- US District Court, Southern District of New York
- US District Court, Eastern District of New York
- J.D., Cornell Law School, 2021, cum laude; Editor, Cornell Law Review; 2021 Cuccia Moot Court Champion
- B.A., Loyola University, Maryland, 2018, summa cum laude; Honors College, Political Science & Italian Studies
Representative Matters
*Includes matters handled before joining Steptoe.
- Member of team that successfully defended financial guaranty insurance company in five-week bench trial against counterparty which sought $485 million in damages related to credit default swap valuation.
- Represented telehealth company in investigation by EDNY into company's prescription drug practices, ultimately resulting in a non-prosecution agreement.
- Defended e-commerce company in nationwide price-gouging class action lawsuit, leading extensive third-party discovery practice.
News & Publications
Client Alerts
FinCEN Issues Notice on Threats of Human Trafficking During the 2026 FIFA World Cup
June 4, 2026
By: Yousuf Aftab, Jonathan C. Drimmer, Andrew C. Adams, Ross Weingarten, Alex Wolf, Patrick F. Linehan, John D. Geilman, Danika Duffy Caledonia, John Mucciolo, Erin Rausch
Global Trade & Investment Law Blog
Foreign Investment in Professional Sports:
May 29, 2026
By: Andrew C. Adams, Patrick F. Linehan, Ross Weingarten, Alex Wolf, Danika Duffy Caledonia, John D. Geilman, John Mucciolo, Kaitlyn Sever
Client Alerts
First CSC NIL Arbitration Upholds Enforcement Authority
May 15, 2026
By: Matt Galvin, Patrick F. Linehan, Ross Weingarten, Alex Wolf, Danika Duffy Caledonia, Kylie Clouse, John D. Geilman, John Mucciolo
Client Alerts
State and Federal Regulators Face Off Over Prediction Markets
May 5, 2026
By: Andrew C. Adams, Matt Galvin, Ryan Hayden, Patrick F. Linehan, Ross Weingarten, Alex Wolf, Danika Duffy Caledonia, John D. Geilman, John Mucciolo
Client Alerts
March Madness in the Law: How Legal Upheaval Is Rewriting College Sports
March 19, 2026
By: Patrick F. Linehan, Ross Weingarten, Alex Wolf, Andrew C. Adams, Danika Duffy Caledonia, John D. Geilman, John Mucciolo
Client Alerts
Litigation Risk and Regulatory Gaps in the Era of "Street Agents"
March 5, 2026
By: Andrew C. Adams, Patrick F. Linehan, Ross Weingarten, Alex Wolf, Danika Duffy Caledonia, John D. Geilman, John Mucciolo
Client Alerts
It's Not on the House — The Risks of Ambiguity in Prediction Markets
February 20, 2026
By: Andrew C. Adams, Patrick F. Linehan, Ross Weingarten, Alex Wolf, Danika Duffy Caledonia, John D. Geilman, John Mucciolo
Client Alerts
January 28, 2026
By: Andrew C. Adams, Patrick F. Linehan, Ross Weingarten, Alex Wolf, John Mucciolo
Client Alerts
Another Open Question in NIL Enforcement—What Exactly Can the CSC Enforce?
January 23, 2026
Press Releases
Steptoe's Win for DISH in Dispute with Disney Earns AmLaw Litigator of the Week Shout-Out
November 24, 2025