About Windsor Kimball APC
About Windsor Kimball APC
About Windsor Kimball APC
We are a boutique criminal defense firm serving clients in federal district court, California state court, and throughout the Ninth Circuit. Our practice is built on individualized attention, disciplined preparation, creative strategy, and direct client access at every stage of the case.
We are a boutique criminal defense firm serving clients in federal district court, California state court, and throughout the Ninth Circuit. Our practice is built on individualized attention, disciplined preparation, creative strategy, and direct client access at every stage of the case.
We are a boutique criminal defense firm serving clients in federal district court, California state court, and throughout the Ninth Circuit. Our practice is built on individualized attention, disciplined preparation, creative strategy, and direct client access at every stage of the case.
Our Approach
Our Approach
Federal criminal cases are among the most serious matters an individual can face. The government has vast resources at its disposal, and the stakes are extraordinarily high. We understand that reality and approach each case with urgency, creativity, and a full appreciation of what is on the line.
Federal criminal cases are among the most serious matters an individual can face. The government has vast resources at its disposal, and the stakes are extraordinarily high. We understand that reality and approach each case with urgency, creativity, and a full appreciation of what is on the line.
Our practice is intentionally small. We do not rely on associates or farm out the work. We keep our caseload at a level that allows us to devote substantial time to each client, thoroughly investigate the facts, and build a defense strategy that accounts for trial, sentencing, and appellate issues from the outset.
Our practice is intentionally small. We do not rely on associates or farm out the work. We keep our caseload at a level that allows us to devote substantial time to each client, thoroughly investigate the facts, and build a defense strategy that accounts for trial, sentencing, and appellate issues from the outset.
We believe in open communication with our clients and their families. Our clients receive direct access to us, personalized attention, and practical guidance about every phase of the federal process, from pre-indictment investigation through appeal.
We believe in open communication with our clients and their families. Our clients receive direct access to us, personalized attention, and practical guidance about every phase of the federal process, from pre-indictment investigation through appeal.
We also understand that fee structure affects strategy. Rather than defaulting to a flat-fee model that can discourage work-intensive defense, we remain flexible in how we work with a client’s budget so they can obtain the strongest possible representation.
We also understand that fee structure affects strategy. Rather than defaulting to a flat-fee model that can discourage work-intensive defense, we remain flexible in how we work with a client’s budget so they can obtain the strongest possible representation.

Our Attorneys
Our Attorneys

Mark Windsor
Partner
mark@windsorlaw.us (626) 792-6700
Mr. Windsor is a veteran criminal defense lawyer, widely regarded in the legal community as a fierce, creative, and relentless advocate for his clients. He began his career in 1997 as a trial lawyer at the renowned Federal Defenders of San Diego, Inc. There he quickly distinguished himself with victories at both the trial and appellate levels. In one notable case, the former Chief Justice for the Ninth Circuit Court of Appeals declared in his written opinion that Mr. Windsor and co-counsel had “fought like tigers” for his client in an alien smuggling trial.
Mr. Windsor is a veteran criminal defense lawyer, widely regarded in the legal community as a fierce, creative, and relentless advocate for his clients. He began his career in 1997 as a trial lawyer at the renowned Federal Defenders of San Diego, Inc. There he quickly distinguished himself with victories at both the trial and appellate levels. In one notable case, the former Chief Justice for the Ninth Circuit Court of Appeals declared in his written opinion that Mr. Windsor and co-counsel had “fought like tigers” for his client in an alien smuggling trial.
Since 2000, Mr. Windsor has been in private practice representing the accused in federal district court in the Northern, Southern, and Central Districts of California, as well as in the Ninth Circuit Court of Appeals and in California State Courts. He has broad experience in all areas of criminal defense, including complex litigation in RICO conspiracy, narcotics offenses, international wire and bank fraud, tax evasion, VICAR murder, and Fourth and Fifth amendment challenges to government overreach.
Since 2000, Mr. Windsor has been in private practice representing the accused in federal district court in the Northern, Southern, and Central Districts of California, as well as in the Ninth Circuit Court of Appeals and in California State Courts. He has broad experience in all areas of criminal defense, including complex litigation in RICO conspiracy, narcotics offenses, international wire and bank fraud, tax evasion, VICAR murder, and Fourth and Fifth amendment challenges to government overreach.
Mr. Windsor currently shares his experience and expertise as an Adjunct Assistant Professor of Constitutional Law at a local law school in Los Angeles.
Mr. Windsor currently shares his experience and expertise as an Adjunct Assistant Professor of Constitutional Law at a local law school in Los Angeles.
Mr. Windsor spent his childhood on Martha’s Vineyard, an island off the coast of Cape Cod, Massachusetts. He graduated from Brown University with a B.A. in history, and then spent several years working abroad and traveling extensively. Mr. Windsor finally settled in California, where he attended law school at the University of California, Davis (Martin Luther King, Jr. School of Law). He now lives and works in Pasadena, California.
Mr. Windsor spent his childhood on Martha’s Vineyard, an island off the coast of Cape Cod, Massachusetts. He graduated from Brown University with a B.A. in history, and then spent several years working abroad and traveling extensively. Mr. Windsor finally settled in California, where he attended law school at the University of California, Davis (Martin Luther King, Jr. School of Law). He now lives and works in Pasadena, California.
Bar Admissions
• State Bar of California • California State Courts • U.S. District Court, Northern District of California • U.S. District Court, Central District of California • U.S. District Court, Southern District of California • U.S. Court of Appeals, Ninth Circuit
Education
• J.D., University of California, Davis • B.A. in History, Brown University

Katy Kimball Windsor
Partner
katy@windsorlaw.us (213) 663-9219
For nearly thirty years, Ms. Kimball Windsor has represented clients fighting criminal charges in federal court. Focused primarily on appellate practice, she has handled a wide variety of cases from white collar fraud to RICO, drug trafficking, and immigration crimes.
For nearly thirty years, Ms. Kimball Windsor has represented clients fighting criminal charges in federal court. Focused primarily on appellate practice, she has handled a wide variety of cases from white collar fraud to RICO, drug trafficking, and immigration crimes.
She has represented numerous clients in the Ninth Circuit Court of Appeals, and is also an experienced trial lawyer who has litigated in the Central and Southern Districts of California. Before entering private practice, she served as a trial attorney at Federal Defenders of San Diego, Inc. from 1996 to 2002, and as a Supervising Attorney at the same office from 2002 to 2003.
She has represented numerous clients in the Ninth Circuit Court of Appeals, and is also an experienced trial lawyer who has litigated in the Central and Southern Districts of California. Before entering private practice, she served as a trial attorney at Federal Defenders of San Diego, Inc. from 1996 to 2002, and as a Supervising Attorney at the same office from 2002 to 2003.
Ms. Kimball Windsor received her B.A. from Vassar College, and her J.D. from University of California, Davis, Martin Luther King, Jr. School of Law.
Ms. Kimball Windsor received her B.A. from Vassar College, and her J.D. from University of California, Davis, Martin Luther King, Jr. School of Law.
Education
• J.D., University of California, Davis • B.A., Vassar College
Experience
• Federal Defenders of San Diego, Inc., Trial Attorney • Federal Defenders of San Diego, Inc., Supervising Attorney • Private practice focused on federal criminal defense and appeals
Jurisdictions Served
Jurisdictions Served
We are admitted to practice and regularly appear in the following courts:
We are admitted to practice and regularly appear in the following courts:
Trial Courts
• U.S. District Court, Central District of California • U.S. District Court, Southern District of California • Northern District of California • Superior Court of California
Appellate Courts
• U.S. Court of Appeals, Ninth Circuit