Jonathan Cantil

Jonathan P. Cantil is an attorney at Rupp Pfalzgraf LLC, where he focuses on complex civil litigation and supervises the firm’s civil rights section. His practice draws on more than a decade of experience handling high-stakes matters across federal, military, and administrative courts, including significant trial and appellate work.

Prior to joining Rupp Pfalzgraf, Jonathan served as a Special Trial Attorney with the Internal Revenue Service, where he led teams in high-value Tax Court litigation involving international transfer pricing and cross-border disputes. In that role, he managed large-scale discovery, examined high-level witnesses, and developed litigation strategy in complex, multi-billion-dollar cases.

Jonathan previously served for over seven years as an Assistant United States Attorney in the Western District of New York, where he prosecuted a wide range of federal offenses, including cybercrime, financial fraud, tax offenses, and child exploitation cases. He served as the district’s Digital Asset Coordinator, leading investigations involving emerging technologies and international actors. During his tenure, he tried multiple jury cases to verdict, securing convictions in complex matters, and argued before the United States Court of Appeals in the Second and Third Circuits, obtaining favorable precedent.

In addition to his civilian practice, Jonathan is a Commander in the United States Navy Reserve Judge Advocate General’s Corps. His military service includes advising senior leadership on operational and international law. He has also litigated national security matters, including capital cases, before military commissions at Guantanamo Bay.

Jonathan has extensive courtroom experience across trial and appellate forums.  At Rupp Pfalzgraf, he brings that depth of experience to his civil litigation practice, where he combines strategic insight, disciplined advocacy, and leadership in overseeing complex civil rights matters.

He earned his Juris Doctor, cum laude, from the University at Buffalo School of Law, where he served as Managing Editor of the Buffalo Law Review.