John J. O'Brien

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John specializes in personal injury, complex business disputes, and sex trafficking litigation. A 14-year lawyer, he has always focused his practice on helping individuals and business owners recover from harm caused by others. In his signature case to date, John received an Outstanding Trial Lawyer award in Jane Does No. 1-22 v, where his clients were awarded $20 million in damages. As a result of the case John put together, during the GirlsDoPorn trial, federal authorities indicted the defendants for sex trafficking and conspiracy.

Raised in Baltimore, Maryland, John graduated from Boston College in 2003 with a degree in Economics and later received his law degree from California Western School of Law in 2007, where he was on the Dean's List and Moot Court Honor's Board.

Passionate about helping the underdog and mistreated, whether his client is an individual or business, John gives every case the same attention he would afford to a family member or best friend. John's plaintiff-focused practice has pursued defendants for personal injury, business fraud, breach of fiduciary duty, infliction of emotional distress, unfair business practices, misappropriation of trade secrets, misappropriation of likeness, breach of contract, and real estate fraud. As just a few examples of John's expansive practice, he has successfully prosecuted start-up businesses for deceitful investment opportunities, sellers for concealing the condition of property, and business partners for circumventing partnership opportunities. He is currently suing several residential hotels for violations of California's "28-Day Shuffle" law. John's wide-ranging case experience allows him to successfully strategize complex cases, resolve novel issues, and exploit defense weaknesses.

As defendants John sues soon discover, John is a fierce competitor. In the GirlsDoPorn case alone, he opposed over 100 motions (including motions to disqualify his team), filed over 30 motions, and took depositions throughout the country. Despite GirlsDoPorn's many attempts to derail John from getting the case to trial, the case culminated in a 99-day trial, with 57 witnesses and over 3,000 exhibits. John tackles each case with courage, fortitude, and hard work - both in out of the courtroom.

Outside the office, John fuels his competitive spirit on the ice and at the gym - he is captain of his ice hockey team and is a regular at a local Olympic weightlifting gym. Maintaining balance, John enjoys sailing as member of San Diego Yacht Club, hot yoga, live music, and has played guitar since the sixth grade. This well-rounded balance enables him to passionately take on opponents, while having compassion for his clients. John tackles each case with courage, fortitude, and hard work - both in and out of the courtroom.


  • Associate Attorney


  • California
  • U.S. District Court Southern District of California
  • U.S. District Court Northern District of California


  • California Western School of Law, San Diego, CA
    J.D. - 2007
  • Boston College, Chestnut Hill, Massachusetts
    B.A. - 2003


  • Welsh Inn of Court – Master Status
  • Association of Business Trial Lawyers
  • Irish American Bar Association of San Diego – President
  • Consumer Attorneys of San Diego
  • Consumer Attorneys of California
  • San Diego County Bar Association


  • Super Lawyers, 2022
  • 2021 Outstanding Trial Lawyer (Consumer Attorneys of San Diego)
  • Super Lawyers Rising Star, 2017 - 2021


  • Free to Thrive (San Diego non-profit assisting sex and human trafficking victims)