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Mark Harris

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Mark Harris is a partner in the Litigation Department, co-chair of the Appellate Practice Group, and a member of the Securities Litigation and White Collar Defense & Investigations Groups.  He represents institutional and individual clients in both civil and criminal litigations.

Mark is a former clerk to U.S. Supreme Court Justices John Paul Stevens and Lewis Powell, Jr., and Judge Joel Flaum of the U.S. Court of Appeals for the Seventh Circuit. Mark subsequently served as an Assistant U.S. Attorney for the Southern District of New York, during which he prosecuted a broad spectrum of federal crimes, including health-care fraud, financial fraud, and corporate embezzlement, and tried a number of jury trials and argued before the Second Circuit.

Mark has handled dozens of cases in the U.S. Supreme Court and other appellate courts in a variety of areas spanning criminal law, patent, copyright, labor relations, and administrative law, including:

  • Representing Biosig Instruments before the U.S. Supreme Court and the Federal Circuit, in a case that redefined the standard for patent definiteness and upheld the validity of Biosig’s patent.  He was named The American Lawyer’s Litigator of the Week for that result.

  • Obtaining reversal of the trial conviction of a former Gen Re executive in the Second Circuit.

  • Persuading the Second Circuit via a petition for interlocutory review and merits brief to vacate a class-certification order entered against Sprint Corporation.

  • Successfully representing electronic publishers before the U.S. Supreme Court in Reed Elsevier Inc. v. Muchnick, which Managing Intellectual Property Magazine named the 2010 "U.S. Copyright Case of the Year."

  • Successfully representing an employer before the U.S. Supreme Court in 14 Penn Plaza LLC v. Pyett, which overturned 35 years of precedents concerning the enforceability of arbitration clauses in labor agreements.

Mark has handled numerous matters involving securities fraud, tax evasion, insurance fraud, and a variety of financial crimes. Significant representations have included the following:

  • John and Timothy Rigas, principals of Adelphia Communications Corp., at their resentencing and before the Second Circuit.

  • The president of a major international company whom federal authorities sought to extradite for tax offenses allegedly committed in the United States.

  • The former CEO of Princeton Economics International, whose release Mark helped win from the longest term of federal civil contempt in U.S. history.

  • An investor charged with securities fraud involving the conversion of a mutual savings bank to a capital stock bank.

Since 1996, Mark has been a member of the Board of Editors of the Federal Sentencing Reporter and a frequent contributor. His work on behalf of non-U.S. clients was featured in the American Lawyer's 2006 Litigation supplement. He has lectured on both criminal law and appellate practice before the International Bar Association, the National Association of Criminal Defense Lawyers, PLI, and the ABA Sections of Litigation, Criminal Law, and Employment and Labor Law, and has been interviewed by Bloomberg Radio, the National Law Journal, WINS AM-1010, Law360, Legal Times, and other news organizations.

He also serves on the Board of Trustees of the National Museum of Mathematics.

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Earlier this month, Proskauer submitted an amicus curiae brief on behalf of a group of 33 elite liberal arts college and universities in two cases pending before the U.S. Supreme Court concerning the constitutionality of affirmative action in college admissions. The petitioners in each case (one challenging Harvard’s admissions process, the other the University of North Carolina’s) contend that consideration of race in admissions violates Title VI of the Civil Rights Act and the Fourteenth Amendment of the Constitution, respectively. They ask the Court to invalidate those policies and overrule a long line of Supreme Court precedent, starting with Regents of University of California v. Bakke, 438 U.S. 265 (1978), and reaffirmed in Grutter v. Bollinger, 539 U.S. 306 (2003), and Fisher v. University of Texas, 579 U.S. 365 (2016).

On August 24, 2020, the United States Court of Appeals for the Fourth Circuit, sitting en banc, reinstated defendant Ronnie Long’s petition for a writ of habeas corpus, challenging his rape conviction more than four decades earlier.  Proskauer filed an amicus curiae brief in support of Mr. Long on behalf of some forty leading scholars who specialize in forensic science, emphasizing the grave impact of the prosecution’s repeated failures to disclose all the forensic evidence in the case.  The Fourth Circuit agreed, and now Mr. Long is expected to be released imminently.

Over forty years ago, Mr. Long was accused of committing a rape and burglary that he has consistently maintained he did not commit.  Relying heavily on the victim’s identification testimony, and the asserted “honesty” of law enforcement who investigated the crime, a jury found Mr. Long guilty of first-degree rape and first-degree burglary.  He was sentenced to life in prison, and his conviction was upheld on appeal.  As the result of continued litigation over the span of many decades, however, a steady stream of suppressed evidence concerning the crime, neither disclosed to the defense nor presented to the jury, came to light. It included lab-test results demonstrating that Mr. Long was not linked to the crime scene; medical evidence taken from the victim that unaccountably went missing; and, most recently, 43 latent fingerprints lifted from the scene, none of which matched Mr. Long.  It also became plain that the detectives who investigated the crime lied at trial about the evidence suppression.