Michael D. Longyear

Michael’s practice focuses on complex criminal, commercial, and regulatory enforcement matters. A former federal prosecutor who led two units in the U.S. Attorney’s Office for the Southern District of New York (SDNY), he helps clients resolve intricate, sensitive, and high-stakes legal challenges.

Prior to joining LSW, Michael served for nearly seven years as an Assistant United States Attorney in the Criminal Division of the U.S. Attorney’s Office for the SDNY.  As an AUSA, Michael supervised scores of Assistant U.S. Attorneys and oversaw dozens of jury trials, most recently as Chief of the SDNY’s Violent and Organized Crime Unit, and prior to that as Co-Chief of the Narcotics Unit.  Michael personally prosecuted or supervised hundreds of cases involving a range of criminal offenses, including racketeering, financial crimes, violent crimes, and narcotics trafficking.  In his supervisory capacity, Michael served as one of the SDNY’s primary liaisons with various federal and state agencies, including the Federal Bureau of Investigation, Homeland Security Investigations, the Drug Enforcement Administration, the Bureau of Alcohol, Tobacco, Firearms, and Explosives, and the New York City Police Department.

Michael’s prosecutorial experience includes the investigation of matters involving fraud, RICO, and other complex multi-defendant conspiracies, money laundering, asset seizure, forfeiture, and cryptocurrency.  Michael interacted frequently with foreign law enforcement agencies on cross-border investigations and issues relating to fugitives and extradition proceedings.

Prior to serving at the U.S. Attorney’s Office, Michael was an associate at LSW, where he represented individuals in white collar and regulatory investigations.  Michael was an associate on the LSW trial team that won the acquittal of the firm’s client on insider trading charges relating to a major hedge fund.

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A Closer Look at Novel Jury Instructions in Forex Rigging Case, Law360  (February 12, 2024) (co-author with Zachary Baron Shemtob, John S. Siffert)

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  • Federal Drug Agents Foundation
    • True American Hero Award (2021)
  • Federal Law Enforcement Foundation
    • Federal Prosecutor of the Year (2020)
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