California State Bar Admission 1995
U.S. Supreme Court, 2008 – present
U.S. Court of Appeals, Ninth Circuit, 1999 – present
U.S. District Court, Central District of California, 1995 – present
U.S. District Court, Southern District of California, 1999 – present
U.S. District Court, Eastern District of California, 2006 – present
U.S. District Court, Northern District of California, 2006 – present
Colorado State University (B.A., 1989)
University of California School of Law, Davis, California (J.D., 1995)
Moot Court Board; National Moot Court and Trial Competitions
Law Clerk, Colorado Attorney General’s Office, Denver, 1993
Legal Intern to Justice Davis, California 3rd District Appellate Court, Sacramento, 1994
Law Clerk, California Attorney General’s Office, Sacramento, 1994
Legal Intern, Sacramento District Attorney’s Office, 1995
Articles
“Successful Handling of Wrongful Death Cases in California: Quirks of Courts” Lorman Education Services, January, 2002
“Biting the Magic Bullet: A Look at the SSRI Litigation” Harris Martin’s Columns: Drugs & Supplements. August 2002
“The Fox in the Chicken Coop” FDA’s Recent Intervention in Pharmaceutical Litigation, ATLA Education, 2003
“The Antidepressant Controversy: The Growth Of A New Area Of Litigation,” Mealey’s Litigation Report Antidepressant Drugs, 2004
“A Cure Worse Than the Disease – Recent FDA actions and newly disclosed research on the link between antidepressants and suicide – especially among young people – are strengthening plaintiffs’ claims against drug makers” TRIAL, 2005
“The FDA’s Dilemma: Safety Failures, Public Scrutiny, and Industry Influence” ATLA Education, 2005
“Internet Disclaimers: Do they waive the attorney-client privilege protection?” ABA Conference “The Future of Class Action Litigation in America”
“Preemption and the FDA — Politics as Usual” ATLA Annual Conference, February, 2006
“Preamble To FDA Final Rule: FDA s Latest Effort To Immunize Drug Manufacturers From Tort Liability At The Expense of Consumer Safety” Mealey’s Emerging Drugs & Devices, February 2006; Mealey’s Litigation Report: Antidepressant Report, February 2006
“Discovery of FDA and Other Regulatory Agency Evidence,” ATLA Education Reference Materials, ATLA 2006 Annual Convention
Birth Defects And Other Threats To Mom And Baby Associated With Paxil, Mealey’s Litigation Report: Antidepressant Report, October 2006
“Preemption and Negligent Pharmacovigilance” ATLA Education Seminar, Protecting the Public: Pharmaceutical and Medical Device Litigation, November, 2006
Focus on Facts to Defeat Preemption, TRIAL, March 1, 2007
2026 Lawdragon 500 Leading Plaintiff Consumer Lawyers list
Karen Barth Menzies is a partner with Justice Law Collaborative. With nearly three decades of legal experience behind her, Barth Menzies founded her own firm, KBM Law, through which she represented survivors of sexual abuse and harassment and challenged the industries that shelter and enable predators. She also has years of experience in mass tort law, focusing specifically on women’s health issues and drugs that cause harm to women and children.
Barth Menzies has been appointed by Courts across the country to serve in leadership positions in some of the largest pharmaceutical and device mass tort cases. These include the Taxotere Hair Loss Litigation (federal court in New Orleans), the Zoloft Birth Defect Litigation (federal and California state courts), Transvaginal Mesh Litigation (federal and California state courts), Fosamax Femur Fracture Litigation (California state court), Lexapro/Celexa Birth Defect Litigation (Missouri state court); and Paxil Birth Defect Litigation (federal and Pennsylvania state courts) the Paxil Withdrawal Litigation (California federal court) and Paxil Suicide Litigation (federal and state courts around the country).
She firmly believes in advocating for workplace and drug safety and for the victims who fall prey to for-profit-driven corporations. Barth Menzies has testified before FDA advisory boards as well as the California State Legislature on drug safety concerns and regarding pharmaceutical manufacturers’ misconduct.
Her ongoing legal and advocacy work supported the passing of the California Sexual Abuse and Cover Up Accountability Act (AB 2777) in 2022. This law enables more victims of adult sexual abuse to file civil lawsuits, regardless of when the abuse occurred, and seek justice and compensation for the harm they suffered.
Karen is a member of the Los Angeles County Bar Association (LACBA).
Karen Barth Menzies is an innovative attorney dedicated to advocating for women’s health causes and representing survivors of sexual assault. Always seeking justice for her clients, Karen has taken on the most powerful pharmaceutical companies in the world and some of the music entertainment industry’s most notorious personalities.
As a litigation leader, Karen has held top positions in mass tort lawsuits involving thousands of women pursuing claims against drug makers and medical device manufacturers. Her advocacy extends beyond the civil court system and into the halls of state legislatures, congress, and government agencies that determine the laws and regulations that protect and empower individuals. Advocacy beyond litigation also involves amplifying women’s voices and supporting their efforts to champion the justice issues that matter most to them.
When many people make claims against a common defendant for similar injuries, those lawsuits are often grouped into what’s called a mass tort. There can be dozens or even hundreds of attorneys representing thousands of plaintiffs in a mass tort. To streamline the litigation process, key attorneys are selected to lead the fight. Karen has served in top leadership positions in mass tort litigation against the major pharmaceutical companies that produce the drugs Paxil® (GSK), Fosamax® (Merck), Zoloft® (Pfizer), Taxotere® (Sanofi), and others.
Notably, Karen took on GlaxoSmithKline for failing to warn doctors and patients about the severe and at times deadly risks of birth defects of its anti-depressant drug Paxil® if taken during pregnancy. Serving as Plaintiff’s co-lead counsel, Karen successfully resolved her cases with the highest settlement values.
Now Karen is focusing her extensive experience and leadership on holding pharmaceutical giant Pfizer accountable for failing to warn women that use of the contraceptive Depo-Provera® can produce brain tumors.
Karen is no stranger to taking on Pfizer. The pharmaceutical giant manufactures the SSRI antidepressant Zoloft®, which carries the potential side effect of akathisia—a drug-induced reaction where the patient causes harm to themselves or others. In one notable case, a woman named Kim Witczak filed a failure to warn claim against Pfizer when her husband took his own life after being prescribed Zoloft®. Karen represented Kim and won her case in a pretrial settlement.
After the settlement, Kim wanted to do more, so Karen supported her efforts to increase awareness of the rare but deadly effects of anti-depressants–especially in children. Together they met with members of Congress, Alex Azar, M.D., and Robert Temple, M.D., of the FDA. Alongside other advocates, Karen and Kim testified about these risks before the FDA Pediatric Drug Advisory Committee. Afterward, the FDA directed the manufacturers of SSRI anti-depressant drugs to include a black box warning and to expand the warning statements on the label about an increased risk of suicidal thinking and behavior in adolescents and children taking the drugs.
Kim Witczak went on to co-found Woodymatters, a non-profit organization that advocates for a stronger FDA and drug safety system. Later, she was appointed and continues to serve as the consumer representative on the FDA Psychopharmacologic Drug Advisory Committee.
Since founding KBM Law, Karen has emerged as a national leader in representing survivors of sexual assault. In 2023, the state legislatures in New York and California opened a window that suspended the statute of limitations for filing sexual assault civil lawsuits in certain circumstances. Based in Los Angeles, as a partner in a prominent plaintiff’s firm, Karen contributed to the effort to enact the California law. Now, in her own firm, she represents survivors in their sexual assault cases against high-profile predators.
Karen knows that seeking compensation after a sexual assault is just one facet of fighting for justice. The women Karen works with are more interested in having their voices heard, demanding accountability, and ensuring others don’t suffer at the hands of a serial predator. Drawing on her extensive experience with high-profile litigation, Karen has helped women manage public interest in their cases and tell their stories.
Recently, Karen founded Unsilenced Survivors, a podcast dedicated to elevating the voices of sexual assault survivors, advocates, and allies.
The podcast is a forum that provides survivors a place to tell their stories, showcases the important work advocates are doing to raise awareness about the pervasiveness of sexual assault, and fosters the development of vocabulary used to talk about sexual assault. Through these efforts, Unsilenced Survivors aims to inspire meaningful societal change and broaden the collective understanding of the conversation about sexual assault.
Early in her career, Karen had to fight against the grain in the competitive, male-dominated civil plaintiffs’ bar. “As a woman,” Karen says, “you had to fight harder to be recognized and for your voice to be heard.” Around that time, Ruth Bader Ginsburg earned her seat on the United States Supreme Court, and Karen found inspiration in the judge’s storied career.
“By her gender, by her size—she personifies the person you would underestimate the most,” Karen says, “but proved time and again her brilliance in achieving justice for the vulnerable and disenfranchised by using the system’s tools against those in power.”
Karen was impressed by Ginsburg’s ability to make incremental changes from inside the system. “She figured out ways to get justice completely against the grain by tapping into her opponents’ beliefs without them even realizing it,” Karen says. She points to the 1972 Moritz case that Ginsburg prosecuted on behalf of a man who accused the IRS of gender discrimination for denying his deductions for expenses related to the care of his elderly mother—solely because he was a man. Until then, the government generally only recognized women as caregivers.
Ginsburg won the case, and the ramifications have benefited the cause of gender equality. “She used a case involving a man’s civil rights,” Karen says, “ to score a victory for women in their fight for civil rights.” When the government recognizes that both men and women can be primary caregivers, it allows women more equal footing with men in their professional careers. Ginsburg said, “Women will have achieved true equality when men share with them the responsibility of bringing up the next generation.”
Karen believes Ginsburg’s creativity as a litigator made her a more remarkable Supreme Court Justice. “I don’t know if she would have been as good at being ‘The Dissenter’ in the Supreme Court,” Karen says, “ if she hadn’t already gone against the grain for so long and had the courage to stick to stand her ground, never deviating from her core values.”
A few years ago, Karen translated her love of listening to punk music to playing punk music—and all sorts of other musical genres. She took up the bass and joined forces with a handful of other female lawyers (including Kim Dougherty) to form a rock band. A few times a year, they unite at legal conferences and entertain friends and curious onlookers with their favorite cover tunes. The band is called … The Dissenters.
