Law Practice:

Eamon represents individuals and businesses in matters of  product liability, tort, and business litigation.

Prior to joining Cosgrave, Eamon was a deputy district attorney in Multnomah County. During that time he tried more than 70 cases to verdict, including 49 jury trials.

Education & Bar Admissions:

Eamon received his bachelor’s degree from Northwestern University in History and Legal Studies. He received his JD from UCLA School of Law in 2015. While at UCLA Law School of Law he was a finalist in the Jones Day 1L Moot Court Competition.

Eamon is admitted to the Oregon State Bar.

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Eamon is a coach (and proud alumni) of the Grant High School We the People: The Citizen and the Constitution Team.


Eamon spends his time out of the office hiking and camping, as well as cooking and running.


“Judicial Gatekeepers:  The changing role of judicial officers and expert testimony”
Judge Mark E. Windham & Eamon McMahon, Los Angeles Daily Journal, February 24, 2014