Fern is a Shareholder at Dietze and Davis, Attorneys at Law. In O'Brien's law practice, she is focused on real estate and business law, including securities laws designed to protect investors. Fern represents real estate clients in matters ranging from commercial development to affordable housing. She has aided business clients on a wide variety of issues: from contract negotiations and corporate finance, to helping employees pursue their dreams of becoming business owners.

Prior to her law career Fern was a successful manager and owner of small businesses. She began her career working on a variety of entrepreneurial projects with her brother, James. In 1985, she became the Director of Marketing at New Day Films, later starting a company representing creative talent to the entertainment industry.

Fern is an active member of the community. In 2004, she was the President of the Board of the Boulder Valley Women's Health Center. She is also a former Board President of Project Safeguard, which provides safety and justice for victims of domestic violence. Currently, Fern is an active member of the Rotary Club, Downtown Boulder Business Improvement District, and Boulder Economic Vitality Committee. She is a Board Member of the Boulder County Bar Association and serves on the Pro Bono Panel of Boulder County Legal Services.

Fern is committed to protecting the interests of Colorado's citizens with perseverance and integrity. As Attorney General, O'Brien will stand up for the main street values of Colorado by guarding the right to privacy, protecting consumers from fraud, and defending our wealth of human and natural resources.

Fern earned her Bachelor of Arts in Humanities from the University of Minnesota and her Juris Doctorate from Rutgers Law School, where she was an editor of The Rutgers Law Review.

Fern O'Brien is married to her husband, Morgan, of 24 years. They reside in Gunbarrel and have two children: Ted, a freshman at Colorado State University and Claire, a sophomore at Fairview High School.