The Firm

Widely recognized as one of the country's leading appellate firms, Riordan & Horgan takes pride in its tenacious and creative representation of each of its clients.

In addition to our decades-long record of success in criminal defense, we have also won cases on behalf of clients in a wide range of civil matters ranging from bad faith insurance judgments to class action wage and hour claims and physician and attorney disciplinary proceedings.

Since the 1980s, Dennis P. Riordan has been considered one of leading specialists in appellate law in California, and across the country. Donald Horgan has a 30-year track record of success in criminal cases at the trial and appellate levels, as well as a background in civil defense stretching back to the mid-1980s. Ted Sampsell-Jones, a former Ninth Circuit clerk and a professor at the Mitchell Hamline School of Law, began appearing as co-counsel with the firm in the early 2000s. He has been a key player in a number of the firm's most significant victories since that time and recently formally joined the firm as of-counsel.

Since founding Riordan & Horgan in 2003, we have prevailed in dozens of state and federal appeals in both criminal and civil cases. We have obtained reversals or dismissals in the Ninth and other Circuit Courts of Appeals in white collar prosecutions involving charges of wire fraud, securities fraud, interstate transportation of stolen property, money laundering, extortion, bribery, computer fraud, false statements, arson, drug sales, violations of environmental regulations, and obstruction of justice, among others. On multiple occasions, we have vacated state murder convictions on federal habeas corpus. Our appellate court reversals in state criminal cases include convictions for murder, burglary, assault, theft, sex offenses, money laundering, and illegal videotaping.

In addition to appellate representation, Riordan & Horgan is often retained in complex federal and state matters to present and argue pretrial, trial, and post-trial motions and to prepare and argue jury instructions. That representation has led to the dismissal of charges before, during, and after trial, as well as to the preservation of claims that were later sustained on appeal.

We also have a record of success as lead trial counsel in state and federal court defending against charges of murder, civil rights violations, computer fraud, and conspiracy to defraud the United States. We have twice secured for clients commutations of their life sentences from the governor of California.

In the civil arena, we recently overturned one of the largest bad faith insurance judgments in California history. In the Ninth Circuit, we successfully defended a bad faith judgment favoring the plaintiffs. Riordan & Horgan has also prevailed in state appeals in employment law and physician and attorney disciplinary cases.

Whether we are working on behalf of a well-known athlete or indigent defendant, a politician or corporate executive, we have earned our reputation for passionate advocacy on behalf of each of our clients.