Susan Horst is a specialist in writs of mandamus and prohibition in the California appellate courts.

For more than 31 years, Susan served as the writ attorney for the California Court of Appeal for the First District, Division One, in San Francisco. Susan is one of the only practicing attorneys in California to have devoted virtually her entire career to appellate writs. As writ attorney in the First District, Susan evaluated thousands of pre- and post- trial writ petitions in all types of civil and criminal matters. In the process, she learned precisely what the justices on the Court of Appeal look for before taking the extraordinary step of granting writ relief — and what an opposing party needs to highlight to have the best shot at getting a petition denied.


Susan’s three decades at the Court of Appeal gave her both extensive writing experience and a wide-ranging knowledge of substantive law.

Susan’s casework ran the gamut from business and commercial litigation, to personal injury and employment matters, to real estate, insurance, and products liability cases, to professional negligence, disqualification, and privilege issues. The procedural postures of the writ petitions she handled were equally wide-ranging, and included pleading defects and class certification, sealing of court records, discovery disputes, summary judgment, settlement, and enforcement of judgments.


Her practice today focuses on writ petition consulting in the appellate courts and trial court work in anticipation of writ relief.

Susan also lectures widely on writ practice and procedure. She has presented seminars to the San Francisco City Attorney, District Attorney and Public Defender Offices, the State Bar of California, California Continuing Education of the Bar, The Rutter Group, PINCUS Professional Education, bar associations across California, and the Center for Judicial Education and Research. She is the co-author of two Continuing Education of the Bar (CEB) titles: Appeals and Writs in Criminal Cases and California Criminal Law: Procedure and Practice.


Susan’s career at the Court of Appeal followed motion and jury trial skills she developed early on as an Assistant District Attorney in San Francisco.

She holds her J.D. from the Santa Clara University School of Law, where she graduated summa cum laude — even though she attended law school part-time at night, while working as a full-time administrator at Stanford University during the day. She also has her B.A. in English from Stanford.


In her spare time, Susan volunteers on the Advisory Board of Advokids, a foster children’s advocacy group.

She also provides pro bono advice and representation through the Advokids Appellate Project.


California Court of Appeal

  • First District
Law School

Santa Clara School of Law

  • Summa cum laude


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