After graduating from law school, Garnett started her career as an
associate at
Wachtell, Lipton, Rosen & Katz in New York City from 2000 to 2004. She served as a
law clerk for Judge
Gerard E. Lynch of the
United States District Court for the Southern District of New York. From 2005 to 2017, Garnett was an
Assistant United States Attorney in the U.S. Attorney's Office for the Southern District of New York, which included service as a Chief of the
Violent Crimes/Violent and
Organized Crime Unit from 2011 to 2014 and as a Chief of Appeals from 2016 to 2017. During 2017–2018, she served as Executive Deputy Attorney General for Criminal Justice in the New York State Attorney General's Office. From 2018 to 2021, she was commissioner of the
New York City Department of Investigation. From 2021 to May 2023, she was the deputy United States attorney for the Southern District of New York.
Federal judicial service Garnett was recommended to the
White House by Senator
Chuck Schumer. On July 26, 2023, a hearing on her nomination was held before the
Senate Judiciary Committee. On September 14, 2023, her nomination was reported out of committee by a 12–9 vote. On November 28, 2023, the
United States Senate invoked
cloture on her nomination by a 49–46 vote. Her nomination was confirmed later that day by a 49–46 vote. She received her judicial commission on January 9, 2024.
Notable rulings On January 30, 2026, Judge Garnett ruled that federal prosecutors cannot seek the death penalty and dismissed the
death-eligible counts from
Luigi Mangione's indictment. == Personal life ==