Introduction
Professor Mark Osler's work advocates for sentencing and clemency policies rooted in principles of human dignity. In 2016, 2019 and 2023 the graduating class chose him as Professor of the Year, and in the 2023-2024 academic year he took a one-year leave of absence from St. Thomas to serve as the Deputy Hennepin County Attorney and Director of the Criminal Division.
Osler's writing on clemency, sentencing and narcotics policy has appeared in the New York Times, the Washington Post, the Atlantic, and in law journals at Harvard, Stanford, the University of Chicago, Northwestern, Georgetown, the University of Texas, Ohio State, UNC, William and Mary and Rutgers. His University of Chicago Law Review article (with Rachel Barkow) was highlighted in a lead editorial in The New York Times, in which the Times' Editorial Board expressly embraced Barkow and Osler's argument for clemency reform. He is also the sole author of a new casebook, Contemporary Criminal Law (West), with a 3rd edition (tailored to the NextGen Bar Exam) coming out in 2027.
Osler played a role in striking down the mandatory 100-to-1 ratio between crack and powder cocaine in the federal sentencing guidelines by winning the case of Spears v. United States in the U.S. Supreme Court, with the Court ruling that judges could categorically reject that ratio. He has testified as an expert before the United States Sentencing Commission and several times before subcommittees of the U.S. House Judiciary Committee.
Osler's 2009 book Jesus on Death Row (Abingdon Press) critiqued the American death penalty through the lens of Jesus' trial. His second book, Prosecuting Jesus (Westminster/John Knox, 2016) is a memoir of performing the Trial of Jesus in 11 states. He held the Byrd Preaching Chair at St. Martin's-by-the-Lake Episcopal Church in 2012 and the Ruthie Mattox Chair in Preaching at First Covenant Church-Minneapolis from 2013 to 2025. In 2011, he founded the first law school clinic specializing in federal commutations, and in 2015 he co-founded (with Rachel Barkow of NYU) the Clemency Resource Center, a one-year pop-up law firm that prepared clemency petitions. Between the two projects, over 100 people have been freed from prison.
In 2023, legislation developed and proposed by Osler and his clinic students was signed into law, reforming the clemency system in Minnesota. Those reforms produced a sharp increase in the number of clemency petitions filed and granted. In 2025, Osler was appointed by Governor Walz to a legislatively-created task force to review Minnesota’s mandatory minimum sentence laws. He has offered commentary to national outlets including NPR’s Morning Edition and All Things Considered, CBS News, PBS News Hour, NBC News, CNN, MSNBC, ABC World News Tonight, Al Jazeera, the New York Times, the Wall Street Journal, the Washington Post and Last Week Tonight with John Oliver. He also has been interviewed by news outlets in South Korea, Germany, France, and Canada.
The character of Professor Joe Fisher in the Samuel Goldwyn film American Violet was based on Osler, and in 2014 he was the subject of profiles in Rolling Stone and The American Prospect. In 2026, his current clemency work was profiled by Ruth Marcus in The New Yorker. Osler is a graduate of the College of William and Mary and Yale Law School.