Kareen O’Brien: A Cross-Section Of Legal Force

Kareen O’Brien
2024 Feature Nominations

Why does anyone go to law school? Some see law practice as a path to recognition. Others see glamour, not the hard work a successful practice demands. Still others seem born to it. They have an innate sense at an early age. Law is in their DNA. Kareen O’Brien is one such lawyer. Born to the law, as she lives and breathes.

UC Irvine and Southwestern Law School

After reading Cynthia Fuchs Epstein’s classic “Women in Law” in high school, O’Brien’s career plans solidified. She obtained her bachelor’s degree in political science from the University of California, Irvine – Class of 1991. After spending several years working, including nearly five years as a paralegal for Walt Disney Company in Burbank, she decided to complete her legal education and enrolled at Southwestern Law School in Los Angeles, where she obtained her Juris Doctor in 2004.

O’Brien’s greatest achievement? Finishing law school while raising three small children. “I was pregnant with my youngest in my first year, she’s also my most argumentative child,” says O’Brien. “I often tease her that her superior debating skills were acquired because she has already completed one year of law school.”

City of Angels to the Valley of the Sun

O’Brien began in 2006 with the Los Angeles County District Attorney’s Office as deputy district attorney. For six years, O’Brien was a major crimes prosecutor.

As a prosecutor – in the City of Angels, then in the Valley of the Sun – O’Brien has seen and heard it all. Helping families in crisis since 2006, she is very confident in the courtroom. Separating truth from lies and isolating real controversy from insignificant drama are second nature. O’Brien’s former boss and mentor, Carolyn McNary at the L.A. County DA, taught her how to analyze a case, how to turn passion for the case and sympathy for the victims into effective and compelling arguments for the jury. “Never fear a jury or judge making the decision when both sides cannot agree,” recalls O’Brien.

This attorney knows a bit about handling celebrities in the courtroom, too. At the L.A. County DA, she had comedienne Sarah Silverman on a jury panel once. O’Brien prosecuted a fraud case where the defense counsel was Christopher Darden. She won.

O’Brien’s job was to prosecute serious and violent felons, primarily those who committed acts of domestic violence, sexual abuse and assault. Experiences with victims of domestic violence taught her the most, though. In Arizona, O’Brien continued prosecuting crimes as deputy county attorney in the sex crimes bureau of the Maricopa County Attorney’s Office. With hundreds of court hearings and over 40 jury trials under her belt, she knows how to uncover truths and pursue justice.

Prosecutor’s Office to Family Law Practice

Soon after relocating to Phoenix in 2012, O’Brien knew the time was right for a change. She transitioned into a solo practice.

O’Brien re-entered private practice with characteristic enthusiasm. She was determined to continue assisting families in crisis. “Being a former prosecutor really helped me be a better family law practitioner,” she insists.

The Law Offices of Kareen O’Brien PLLC, in Glendale opened its doors in 2013. In her bustling practice, she also handled legal matters involving special education law, estate planning, construction law and – putting her experience with the criminal justice system to work – criminal defense. In 2016, she joined the Stewart Law Group as an associate attorney. O’Brien works out of the firm’s main office in Phoenix.

With domestic relations cases, two skills O’Brien acquired as a prosecutor are particularly useful – the ability to spot false allegations and to expose ulterior motives. Sadly, in some child custody cases, one parent may falsely accuse the other parent of child abuse; or one parent may attempt to alienate the other parent from their child. Justice for the individuals she represents has always been O’Brien’s priority.

“The most important issues in any divorce are ones involving my clients’ kids,” says O’Brien. She is always in her client’s corner, fighting for the client and for the children’s best interests. Being the mother of three, O’Brien understands fully how emotional, stressful and volatile family law cases can be. When she handles a case that involves an abusive parent, she takes it personally and does everything within her power to make sure the children are protected and placed in an appropriate environment.

Discussing the family court system, O’Brien sees room for improvement. She would like to see greater movement away from win-at-all-costs child custody litigation toward the collaborative model. On social media evidence, family court judges are often overwhelmed with emails, Facebook, Twitter, and Instagram posts, text messages, and audio and video recordings. These types of exhibits can corroborate a litigant’s testimony and may prove that the opposing party is either lying or acting inappropriately. But the sheer volume produced by some parties can overwhelm both court and counsel, driving up litigation costs, and at times, can even divert the attention of the judge away from the truly important issues.

“Judges simply do not have the time or resources to review voluminous exhibits containing text messages, emails and audio and video recordings,” O’Brien says. “Litigants often don’t understand that, which is why it is critical for the attorney to methodically review all the evidence, and select only the most persuasive and corroborating evidence, effectively presenting it to the judge and making sure the judge is not overwhelmed with the sheer volume of it all.”

Looking to the future, O’Brien’s next great aspiration is to tackle the challenges of a judgeship herself. With her broad cross-section of experience from family law to civil practice in her early career, she is a serious contender and hopes to join the ranks of her fellow Southwestern graduates like Hon. Stanley Mosk, Hon. Otis D. Wright, II and Hon. Gordon Thompson.

Who Is Kareen O’Brien?

O’Brien has been described by peers and clients alike as thorough, confident and compelling in the courtroom. She is also empathetic, truly listening to her clients’ concerns. She will explain complex legal concepts ad infinitum to ensure the client understands every good, bad, and ugly truth of the situation.

O’Brien was motivated to join the Stewart Law Group in 2016 for several reasons. Firstly, the ability to collaborate. Secondly, a firm culture of always putting families first – both those of the clients’ and the employees’. “The firm has a commitment to helping people and a high standard for ethical conduct,” she says.

And on the lighter side, she relishes tormenting colleagues as the firm’s unofficial birthday emissary. “I love celebrating my colleagues’ birthdays, whether they like it or not,” she laughs.

Kareen O’Brien is a legal force to be reckoned with, but she is also a funny, dynamic person. A huge Cardinals fan. Adventurous, when not buried in a good book, building Lego kits, or watching old movies. Boundlessly energetic, she competed in both L.A. and San Diego marathons and loves hiking, biking and camping. (On one misadventure, she got lost in Prescott’s “Man Against Horse Race” after a steer ate the trail marker.)

Today, O’Brien channels psychic energy from the bleachers to her two youngest children, both teenagers. Her weekends are filled with their swim competitions, motocross events, and mountain bike races. All is good.


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Katherine Bishop

Katherine Bishop is a staff writer for Attorney at Law Magazine. She has been a writer with the publication for more than four years. She also writes for Real Estate Agent Magazine.

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