David P. Mastagni is the founder and managing partner of Mastagni Holstedt, APC, where he practices primarily in the areas of civil litigation and labor law. David has tried over 300 proceedings to verdict, including over 100 jury trials in both state and federal courts. He has participated in over 450 appellate cases at the state and federal levels, including actions before the U.S. Supreme Court.

As the firm’s lead attorney, David was responsible in 2003 for obtaining the largest law enforcement binding arbitration award in the United States. David advises public and private labor unions on contract issues, grievances, and binding arbitration. David’s involvement in labor and law extends to the state Capitol, where he has testified before the legislature on issues involving peace officers, labor unions, injured workers, and consumer litigation. He has participated in drafting several laws and currently advises clients on election law and political action committees.

David is a lecturer for the Peace Officers’ Research Association of California (PORAC) and a longtime panel attorney for the PORAC Legal Defense Fund. He has lectured widely over the years on issues of concern to public safety officers/public employees and labor unions.

David served in the U.S. Army National Guard in the Vietnam era. While in law school at the McGeorge School of Law, David received the American Jurisprudence Award in Evidence, an award given to the student who achieves the highest grade in the class. He currently sits on the Dean’s Council at the McGeorge School of Law.