Diane McMillan

Diane McMillan is an attorney at Allegiant Law in Portland, Oregon, where her practice focuses on Complex Litigation and Legal Malpractice. She brings a strong analytical background to contested matters and works with detailed factual records that require careful review and clear legal reasoning. Diane’s combination of mathematics training, litigation experience, and public-interest work supports an approach centered on identifying critical issues, organizing complex information, and communicating legal positions effectively.

Diane earned a J.D. from Lewis & Clark Law School in 2024, graduating summa cum laude with pro bono honors and a CALI Excellence for the Future Award. She also earned an M.S. from Oregon State University and a B.S. from the University of Oregon, both in mathematics. Her academic research examined the misuse of statistics in the criminal justice system, experience that strengthens her ability to analyze evidence, patterns, and technical information in complex litigation.

During law school, Diane gained experience through clerkships with Oregon Public Broadcasting, the Federal Public Defender’s Portland office, and civil litigation firm Haglund Kelley. She also volunteered for two years with the Civil Rights Project and Youth Justice Project at the Oregon Justice Resource Center. These roles exposed her to litigation, constitutional issues, public-interest advocacy, and professional responsibility concerns before she entered practice as an Oregon attorney.

Diane McMillan is admitted to practice in Oregon and participates in the Oregon Pro Bono Appellate Panel, Oregon Women Lawyers, and the Oregon Justice Network. Her early legal career combines academic achievement with practical work in litigation, public defense, civil rights, and media-related legal settings. That background supports her current work on complex disputes and legal malpractice matters, where careful factual analysis, sound judgment, and clear written and oral advocacy are especially important.

Law Office Affiliations

• Attorney, Allegiant Law, LLP
• Member, Oregon State Bar
• Member, Oregon Women in Law (OWL)
• Member, Oregon Justice Network (OJN)
• Member, Oregon Pro Bono Appellate Panel

Licensed State

• Oregon

Education

• Lewis & Clark Law School
  Juris Doctor (JD)
• Oregon State University
  Master of Science (MS)
• University of Oregon
  Bachelor of Science (BS)

Awards & Badges