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Peter Lacny is originally from DuBois, Pennsylvania. He is admitted to practice in all Montana federal and state courts, the Ninth Circuit Court of Appeals, and the United States Supreme Court.

Practice Areas

Peter’s broad litigation practice includes criminal and civil cases in state and federal courts.

In his criminal practice, Peter defends individuals and corporations in all types of prosecutions—from misdemeanors to high-stakes felonies. Since beginning practice in 2006, Peter has successfully defended countless criminal cases across Montana. An accomplished trial lawyer, Peter has obtained acquittals for accused clients in both federal and state courts. A significant part of Peter’s current criminal practice is federal cases and grand jury investigations.  

In addition to his traditional criminal defense practice, Peter is frequently called on to represent professionals—including attorneys, doctors, teachers, and law enforcement— facing disciplinary actions from their licensing boards. Peter regularly represents college students facing expulsion for violating student conduct codes.

Peter’s civil practice focuses on plaintiff’s personal injury cases and commercial litigation.  His civil case load includes matters in state and federal courts, at the trial and appellate levels.

Peter is a proud member of the District of Montana’s Criminal Justice Act Panel, where he provides federal criminal defense services to indigent accused citizens.

Peter is recognized by his peers as an expert in federal and state firearm laws, on which he regularly consults with other attorneys. 

Professional Memberships

Lawyer Representative to the Ninth Circuit Judicial Conference (2023-2026)      

Past President and Life Member— Montana Association of Criminal Defense Lawyers

Member—Montana Trial Lawyers Association

Member—Federal Bar Association

Member—National Association of Criminal Defense Lawyers

Member—District of Montana Criminal Justice Act [CJA] Panel


University of Montana School of Law (J.D. With Honors, 2006);

Montana State University (B.A., History, 2002).


ACLU’s 2007 Vern Klingman award for work in securing pardons for Montanans convicted under the sedition act.
The Best Lawyers in America—White Collar Criminal Defense 2022-2023.
Super Lawyer 2013-2022.

Speaking Engagements

University of Montana School of Law:  Peter is a frequent guest speaker at the University of Montana School of Law on a variety of topics related to trial practice and criminal law.

Office of Public Defender “Boot Camp”: Instructor on closing argument at Office of Public Defender training session for new attorneys.

Trying Your Case in Montana Federal Courts: Panel member at Federal Bar Association seminar. Lecture focused on trial practice and techniques in federal court.

The Other Evidence Rules: Instructor at State Bar Criminal Law Section conference in Missoula, Montana. Lecture focused on state evidence rules.

Contemporary Issues in Civil and Criminal Practice: Instructor at Montana Trial Lawyer Association conference in Missoula, Montana. Lecture focused on intersection between civil and criminal practice.

Out of My Cold Dead Hands: Instructor at Montana Criminal Defense Lawyers Annual Seminar in Chico, Montana.  Lecture focused on federal firearms law.


[email protected]

(406) 728-0810