Marguerite L. Jonak

Marguerite L. Jonak

(619) 515-0269

Marguerite L. Jonak is a Partner in the San Diego office of Manning Kass. She is a member of the Special Investigations Unit / Insurance Fraud Litigation and Workers' Compensation teams.

Ms. Jonak's decades of experience started with the recovery of millions of dollars in restitution for numerous carriers and self-insured employers defrauded by prolific medical-legal providers and their co-conspirators, prosecuted and convicted for insurance fraud while she was a deputy district attorney for the County of Los Angeles.

She has since applied her investigative and litigation skills to all facets of first- and third-party insurance investigations. She is tenacious and proactive in handling complex matters involving liability, workers’ compensation, property and other first-party claims. Her clients also seek her counsel in matters including affirmative litigation, audits, subrogation, and risk management. Ms. Jonak is a member of the California State Bar and New York State Bar and is admitted to the United States District Court, Central and Southern Districts of California, and Southern and Eastern Districts of New York.

Ms. Jonak is the Co-Founder of the New York office of Manning Kass. 


  • California State Bar
  • New York State Bar


  • California
  • New York


  • United States District Court for the Central District of California
  • United States District Court for the Eastern District of New York
  • United States District Court for the Southern District of California
  • United States District Court for the Southern District of New York


  • Pepperdine Law, Juris Doctor
  • University of Washington, Bachelor of Arts in Psychology and Society & Justice
    • Member, Psi Chi Honor Society