Michael Attanasio, Partner In Charge - SD

Mike Attanasio is Partner-in-Charge of the San Diego office and Chair of the firmwide Litigation Department. He also serves on the firm's Management Committee. Mr. Attanasio is a Fellow of the American College of Trial Lawyers and has been recognized as a Game Changer by The Recorder, one of the Top 100 Lawyers in California by the Daily Journal, and one of the Top 10 Lawyers in San Diego by Super Lawyers.

Mr. Attanasio represents companies in a wide range of industries in complex business litigation, including securities and consumer class actions, commercial contract litigation, and disputes involving corporate governance and breaches of fiduciary duty. Mr. Attanasio, a former federal prosecutor, also specializes in white collar criminal defense and internal investigations. He has represented individuals and corporations in proceedings and investigations being conducted by various United States Attorney's Offices, the SEC, the FBI, congressional committees, and Major League Baseball. 

Mr. Attanasio is an experienced jury trial lawyer who has tried numerous cases to verdict in courts around the country. Recently, he was co-trial counsel for baseball legend Roger Clemens in the obstruction of Congress and perjury prosecution brought against Clemens by the U.S. Attorney's Office for the District of Columbia. After a nine-week trial, the jury returned not guilty verdicts on all six counts. Mr. Attanasio's cross-examination of prosecution witness Andy Pettitte, a former teammate of Clemens, was called a key turning point in the trial by several observers. Mr. Attanasio also took the lead in debunking DNA evidence that prosecutors claimed linked Clemens to the use of performance enhancing drugs.

In another notable trial victory, Mr. Attanasio led the successful defense of a former Arthur Andersen partner accused by the Justice Department with conspiracy, securities fraud, and wire fraud in connection with the financial reporting of Peregrine Systems, a worldwide software company. The U.S. Attorney described the case as the largest fraud in the history of the Southern District of California. After two trials lasting nearly six months, both juries declined to convict Mr. Attanasio's client on a single count and all charges were dismissed.

"All we need is a level playing field and the case can be resolved or tried fairly. Nothing more, nothing less."

Read a Q&A with Mike Attanasio

From 1991 through 1999, Mr. Attanasio was a federal prosecutor in Washington, DC, for the Public Integrity Section of the U.S. Department of Justice. During his tenure with DOJ, Mr. Attanasio was assigned to handle sensitive investigations and trials in districts around the country. He received several commendations from the Attorney General and various law enforcement agencies, including the Attorney General's John Marshall Award for Legal Achievement (Trial). 

Mr. Attanasio is routinely named among the best in his fields of practice by various publications, including Best Lawyers in America (Bet-the-Company Litigation, Commercial Litigation and White Collar Defense); Benchmark Litigation (California - Litigation; National - White Collar); Southern California Super Lawyers (White Collar Defense and Securities Litigation); and San Diego Daily Transcript "Top San Diego County Attorneys" (Criminal Law). In 2013, TheDaily Journal selected Mr. Attanasio's trial victory for Encore Capital for its exclusive "Top Defense Verdicts" list.

Mr. Attanasio graduated from Stanford Law School in 1990 and thereafter served as a Law Clerk to the Honorable Rudi M. Brewster, United States District Judge for the Southern District of California. He received his BA from Princeton University, Woodrow Wilson School for Public and International Affairs.

Mr. Attanasio is an Adjunct Professor of Law at the University of San Diego Law School, where he teaches White Collar and Corporate Crime. He is also Co-Chair of the White Collar and Corporate Investigations Subcommittee of the Securities Litigation Committee of the ABA Section of Litigation.  He speaks and publishes frequently about trial practice and white collar criminal issues.


  • Stanford Law School
    JD, 1990
  • Princeton University
    BA, 1987

Court Admissions

  • All California State Courts
  • U.S. Court of Appeals, District of Columbia Circuit
  • U.S. Court of Appeals, Fifth Circuit
  • U.S. Court of Appeals, Sixth Circuit
  • U.S. District Court, Central District of California
  • U.S. District Court, District of Columbia
  • U.S. District Court, Northern District of California
  • U.S. District Court, Southern District of California
  • U.S. District Court, Southern District of Texas

Bar Admissions

  • California

Professional Affiliations

  • Fellow, American College of Trial Lawyers
  • ABA, Co-Chair, White Collar and Corporate Investigations Subcommittee of the Securities Litigation Committee
  • American Inns of Court, Louis Welsh Chapter, Master
  • San Diego Volunteer Lawyer Program, Director

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