On Monday, Biden announced the commutation of 37 out of 40 inmates on federal death row, with less than a month left in office. The three left on death row were those responsible for massacres: Dylann Roof, 30, murdered nine black parishioners in Charleston in 2015; Robert Bowers, 52, murdered 11 Jewish congregants at the Tree of Life Synagogue; and Dzhokhar Tsarnaev, 31, one of the brothers behind the 2013 Boston Marathon bombing that killed three and injured hundreds more.

He repeated his stance in a statement on Monday.

“I am more convinced than ever that we must stop the use of the death penalty at the federal level. In good conscience, I cannot stand back and let a new administration resume executions that I halted,” Biden said.

In the same statement, he said the commutations are “consistent with the moratorium my Administration has imposed on federal executions, in cases other than terrorism and hate-motivated mass murder.”

Biden has faced pressure from a number of sources to commute the sentences, from left-wing factions within the Democratic Party to Pope Francis, whom Biden spoke with last week. The president had vowed to abolish the federal death penalty during his 2020 campaign but only issued a moratorium on further executions during his presidency.

President-elect Donald Trump took the opposite approach to the death penalty, overseeing the execution of 13 death row inmates during his first term. He has vowed to expand the death penalty for more crimes in his second administration.

The move to commute the sentences is likely to incur the wrath of Trump and allies, who have argued that Democrats’ approach to the death penalty reflects a soft-on-crime philosophy.

The vast majority of death row inmates will go unaffected by Biden’s commutation, as thousands are on death row in states across the country.

Among those whose sentences were commuted by Biden were Brandon Basham, 43, and Chadrick Fulks, 47, who kidnapped, raped, and murdered two women after escaping prison. Thomas Sanders, 57, murdered a mother in front of her 12-year-old daughter, kidnapped her, then murdered her four days later.

Others were convicted of murdering several people — Kaboni Savage, 49, murdered 12 people in connection with a drug enterprise, including an infant and three other children, after he ordered their apartment to be firebombed. He was later recorded mocking their deaths.

Two serial killers, Jurijus Kadamovas, 58, and Iouri Mikhel, 59, who kidnapped and murdered five people, also had their sentences commuted. Jorge Torrez, 36, was convicted of kidnapping, sexually assaulting, and murdering an 8-year-old and 9-year-old girl, raping another woman, and murdering a female naval officer.