Michael M.



  • Columbia Law School (J.D., 1997)
  • United States Military Academy (B.S., 1991, Economics)
  • Hon. Peter K. Leisure, United States District Court for the Southern District of New York
  • California
  • New York
  • Hawaii
  • United States Supreme Court
“Hailed by peers and clients to be practical and smart with the savvy and experience and good judgment to handle the most complicated matters.”
—Benchmark Litigation
“[F]antastic” lawyer who “gives good big picture advice but knows the details of the case really well, so can dive right in.”
“[O]utstanding judgement; very strong with regulators and the government.”
—Legal 500

Described as a “fantastic lawyer ” who is “very strong with regulators and the government” and “hailed by peers and clients to be practical and smart with ‘savvy experience and good judgment to handle the most complicated matters,’” Michael Purpura is a nationally renowned trial lawyer who has been selected by United States Presidents, Fortune 500 companies, and prominent individuals to solve their most significant legal challenges.

Mr. Purpura’s unique blend of public and private sector experience allows him to provide clients with multi-dimensional counseling on the most complex legal issues. He has served as an adviser to two United States Presidents, navigating the separation-of-powers issues involving the Executive and Legislative Branches in some of the most significant and high-profile legal and political battles in recent memory. As a chief legal officer for an SEC-registered real estate private equity firm, he was responsible for all legal, compliance, risk, and ethics functions. And in prior work as a commercial litigator and as a prosecutor in the Southern District of New York, Mr. Purpura successfully tried numerous cases and precedent-setting appeals.

Mr. Purpura has had an active pro bono practice, including recently serving as counsel of record and filing an amicus curiae brief in the United States Supreme Court on behalf of 35 former high-ranking military officers in Students for Fair Admissions v. President and Fellows of Harvard College and Students for Fair Admissions v. University of North Carolina, et al., arguing that the Court should uphold the constitutionality of the consideration of race in college admissions. In 2016, he filed a similar amicus curiae brief in Fisher v. University of Texas at Austin.

Mr. Purpura has been repeatedly recognized as a Band 1 Leading Individual by Chambers, a Litigation Star by Benchmark Litigation, and a Best Lawyer in six different legal disciplines and a “Lawyer of the Year” by Best Lawyers for both Securities Litigation and Appellate Practice.

Mr. Purpura has been an active member in multiple professional and community organizations, serving in key leadership roles. At the University of Hawaii William S. Richardson School of Law, he taught Constitutional Law and a seminar on White Collar Crime and was an Advisory Board member of the Hawaii Innocence Project. Mr. Purpura also served as President of the Federal Bar Association Hawaii Chapter, was a founding member of the Hawaii Federal Trial Academy, and twice served on the United States Magistrate Judge Selection Panel for the District of Hawaii. Finally, Mr. Purpura is a Trustee of The Linsly School in Wheeling, West Virginia, from which he graduated.

A graduate of the United States Military Academy, Mr. Purpura served in the United States Army as a field artillery officer before attending law school.


Won a “landmark” opioid trial for Endo Pharmaceuticals in a $50 billion action. Three of the most populous counties in California and the City of Oakland brought suit against opioid manufacturers alleging false advertising, unfair competition and public nuisance. The jurisdictions claimed that manufacturers’ alleged false and misleading marketing caused a $50 billion public nuisance. The win was hailed as “giv[ing] drug companies their first major victory in the litigation brought by cities and counties across the country over the opioid crisis,” American Lawyer. (See “How Hueston Hennigan Notched A Landmark Opioid Trial Win,” Law360; “Opioid Makers Win Major Victory in California Trial,” New York Times; “Drug Makers Handed First Win Out of Thousands of National Opioid Crisis Lawsuits,” Newsweek).

Represented the President of the United States and delivered multiple addresses to the United States Senate during the third impeachment trial of a United States President in history.

Represent the former Counsel to the President and former Deputy Counsel to the President before the Select Committee to Investigate the January 6th Attack on the United States Capitol.

Represent a global accounting firm in a Securities and Exchange Commission investigation related to accounting irregularities.

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Represent a pharmaceutical company in litigation related to opioid abuse scheduled for trial in April 2022 at the U.S. District Court in San Francisco.

Represent a prominent individual in connection with a criminal investigation into alleged campaign finance violations.

Won a very favorable defense verdict following a five-week bellwether jury trial in a mass action brought against Fortune 100 client. This result led to a similarly favorable global settlement of all related cases for less than 5% of plaintiffs’ demands.

Obtained a complete arbitration victory for large corporate landowner in a dispute to determine value of land, and thus future rent owed. The arbitrators ruled the property was to be valued at more than the client’s 8-figure demand.

Secured a declination for the target of a federal grand jury investigation into alleged violations of the Clean Water Act and related crimes.

Secured a termination of a lengthy SEC investigation of a high-profile client with allegations of insider trading.

Obtained a no-action letter from the SEC on behalf of the chief compliance officer of a hedge fund in an investigation of allegations of improper trading practices. The SEC brought action against the fund and its CEO.


  • Band 1, Litigation: General Commercial, Chambers USA
  • Litigation Star, Benchmark Litigation
  • “Lawyer of the Year” and a leading lawyer in six disciplines, Best Lawyers
  • Key Lawyer for Corporate Investigations and White Collar Criminal Defense, Legal 500
  • Key Lawyer for General Commercial Disputes, Legal 500
  • The Best Lawyers in America


Board of Governors, Association of Business Trial Lawyers, Orange County Chapter

Trustee, The Linsly School

Former Advisory Board Member, Hawaii Innocence Project

Former President, Federal Bar Association Hawaii Chapter

Founding Member, Hawaii Federal Trial Academy

Former Member, United States Magistrate Judge Selection Panel for the District of Hawaii

Former President, Access Tennis

Hueston Hennigan Named a Law360 Trials Group of the Year