William Mahoney is a litigator who helps clients navigate the legal issues they face in a variety of disputes in federal and state courts. The primary focuses of his practice are antitrust litigation and complex commercial litigation. As a member of Paul Hastings’ Antitrust and Competition team, William has experience representing both plaintiffs and defendants in class actions and litigating before the Department of Justice. William also has experience representing plaintiffs and defendants in a variety of other substantive areas, including restructuring litigation, insurance recovery, internal investigations, white collar defense, trust litigation and constitutional litigation. William has handled all phases of litigation, from pre-suit strategy through trial and into appeal.

William brings first-chair trial experience rare for his level of seniority. In his second year of practice, he led a pro bono civil rights trial in federal court, where, among other roles, he argued pretrial motions, selected the jury, gave the opening statement and examined the plaintiff, defendant and an expert. William continues to take key roles in high stakes matters.

Prior to joining Paul Hastings, William served as a law clerk for the Honorable Judge Drew B. Tipton of the United States District Court for the Southern District of Texas.

Admitted only in Texas. Application for admission filed in the District of Columbia. Practice supervised by members of the District of Columbia Bar.

William earned his J.D. from the University of Virginia School of Law in 2021. During this time, he clerked in the Washington, D.C. office of Sen. Ted Cruz. William earned a Bachelor of Arts in International Studies and Spanish from the University of Mississippi, summa cum laude, in 2017.