About Jon Matthew
Jon Matthew Martinez built a legal foundation that blends political science, psychology and media studies before he earned his law degree. He received dual bachelor’s degrees in political science and psychology from the University of Arizona in 2000. He then remained at Boston University, where he completed a master’s in mass communications and his J.D., both in 2004. Those early choices point to an interest in how people, institutions and messages intersect—an interest that has shaped his career in criminal law.
After law school, Martinez joined public service. In 2007 he worked in the Maricopa County Lawyer’s Office as a major crimes prosecutor. That role placed him in court on serious felony matters and offered a steady diet of fast-moving investigative files. Two years later he switched sides of the aisle and became the lead criminal defense lawyer at a private defense office in Mesa. The move from prosecutor to defender is not unusual, but it gave him experience on both sides of the criminal justice system and a clearer sense of strategy when cases go to trial.
Martinez is admitted to practice in Arizona and before the Ninth Circuit. Those credentials reflect work at both county and federal levels. He also holds memberships in national and state professional groups, including the National Association for Criminal Defense Lawyers, the American Bar Association, the Arizona Bar Association and the American Association for Justice. He maintains those memberships while handling a caseload that spans pretrial work, hearings and court trials.
His courtroom experience includes handling major felony prosecutions earlier in his career and later directing defense strategy as a lead attorney. Colleagues describe him as someone who pays attention to evidentiary detail and to witness preparation. He has navigated jury trials and complex plea negotiations. Martinez’s background in communications and psychology appears in the way he frames testimony and prepares witnesses, and his time as a prosecutor informs how he anticipates the other side’s moves.
Today he operates under the banner of the Jon M. Martinez Criminal Law Group. The practice centers on criminal defense matters in Arizona, and he continues to appear in federal matters before the Ninth Circuit when cases require it. He handles trial-level work and pretrial litigation, and he represents clients in contested hearings as well as negotiated resolutions.
He is currently practicing criminal defense in Arizona and before the Ninth Circuit.
