Julia Mezhinsky Jayne

Julia Mezhinsky Jayne

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American College Of Trial Lawyers

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Julia Mezhinsky Jayne is an experienced trial lawyer specializing in white-collar and general criminal defense. Ms. Jayne is a Fellow of the American College of Trial Lawyers and is ranked in Chambers & Partners for White Collar Crime and Government Investigations. She has been recognized as a Super Lawyer for 13 consecutive years. San Francisco Magazine has celebrated her as a leading woman attorney in Northern California and the L.A. Times named her as a legal visionary in 2023. Notably, her law firm, Jayne Law Group, has been hailed as a premier boutique law firm in California.

A former prosecutor, Ms. Jayne has nearly 25 years of experience navigating complex criminal cases in both federal and state courts. She has taken more than 40 cases to trial before a jury and skillfully maneuvered countless evidentiary challenges through motions practice. 

Ms. Jayne's clientele encompasses a diverse range of individuals and companies, representing their interests at various stages of legal proceedings, from investigations to pre-trial and ultimately, trials. Her successes span from securing outright dismissals of cases to negotiating highly favorable plea agreements and securing acquittals. Ensuring the utmost satisfaction of each client is her unwavering commitment.

In the realm of white-collar criminal defense, Ms. Jayne's expertise encompasses an array of prosecutions, ranging from mail and wire fraud violations to bribery and kickbacks, insider trading, bank fraud, environmental crimes, money laundering, theft of trade secrets, antitrust violations, immigration crimes, false statements, identity theft, criminal contempt, tax evasion, extradition matters, and cases involving significant asset forfeiture implications.

Beyond white-collar defense, Ms. Jayne's extensive experience in general criminal defense covers a wide spectrum of offenses. From violent felonies and vehicular manslaughter to drug distribution, sex offenses, firearms charges, theft and fraud cases, robbery, burglary, and driving under the influence, she has showcased her versatility and acumen.

Before co-founding Campbell & Jayne LLP in 2006, Ms. Jayne served as a Deputy District Attorney in Contra Costa County. During her tenure, she handled an array of misdemeanor, felony, and juvenile cases, skillfully filing criminal charges, negotiating thousands of cases, and diligently trying numerous cases independently. Subsequently, she broadened her legal horizons as a civil litigator at Larson King in San Francisco.

Transitioning to the realm of white-collar criminal defense and civil litigation, she contributed to the representation of several high-profile clients at Sideman & Bancroft LLP. Earlier in her career, Ms. Jayne gained valuable experience as a legal intern for the Organized Crime Strike Force at the Department of Justice's U.S. Attorneys' Office in San Francisco.

Beyond her courtroom victories, Julia Jayne's expertise has attracted considerable media attention. She has been sought after as a legal commentator by prominent media outlets such as CBS News, Law360, LA Times, Yahoo! News, Court TV, Hollywood Reporter, Fox News, and the Daily Beast. Her insights and analyses have brought clarity to complex legal matters and elevated public discourse.

In addition, Ms. Jayne has been sharing her trial skills as an adjunct professor, teaching trial advocacy at U.C. Law San Francisco (formerly U.C. Hastings College of the Law) since 2003. Additionally, she has actively served on the Criminal Justice Act Panel in the Northern District of California for many years. Holding the position of Programs Chair for the Women in White Collar Defense Association's San Francisco chapter, she remains deeply engaged in the legal community.

Ms. Jayne is also fluent in Russian.


  • University of California College of the Law, San Francisco (formerly UC Hastings), San Francisco, California
    • J.D. - 1999
  • Oxford University Faculty of Law, Oxford
    • Spring Semester - 1998
  • University of California, Los Angeles, California
    • B.A. - 1995
    • Honors: magna cum laude


  • Chambers USA – since 2023
  • Fellow of the American College of Trial Lawyers – since 2023
  • Selected to California Super Lawyers – 2015 – Present
  • Selected to California Super Lawyers Rising Stars – 2009 – 2014
  • Top 3 Criminal Defense Lawyers in San Francisco – Three Best Rated – 2021
  • 10.0 Superb AVVO Rating – Top Attorney Criminal Defense

Classes & Seminars

  • Adjunct Professor of Trial Advocacy, University of California Law San Francisco (formerly, Hastings College of the Law), 2003 to Present

Past Positions

  • Contra Costa County District Attorney's Office, Deputy D.A.
  • Sideman & Bancroft LLP, White Collar Criminal Defense Attorney and Civil Litigator
  • Larson · King, San Francisco, Civil Litigator
  • Campbell & Jayne LLP, Partner
  • Organized Crime Strike Force for the Department of Justice, U.S. Attorneys' Office in San Francisco, Legal Intern


  • Russian

Ancillary Businesses

  • Small Business Compliance & Internal Investigations

Professional Associations

  • American College of Trial Lawyers
  • Criminal Justice Act Panel (“CJA Panel”) for the Northern District of California, Member, 2005 to Present
  • California State Bar Criminal Law Executive Committee, Past Chair and Advisor
  • Eastern European Bar Association, Northern California, Member
  • National Association of Criminal Defense Lawyers: Member of Diversity, Women, and White-Collar Committees; and Regional West Coast Delegate of Membership Committee
  • Women’s White Collar Defense Association: Program Chair (San Francisco chapter); global social media committee; Member
  • Provisors