Attorney General Merrick Garland on Thursday issued a moratorium on federal executions, ordering a review of death penalty policy changes made during the Trump administration.

The move is an abrupt shift for the department, which just weeks ago filed court papers seeking to reinstate the death penalty against Boston Marathon bomber Dzhokhar Tsarnaev.

The Justice Department “must ensure that everyone in the federal criminal justice system is not only afforded the rights guaranteed by the Constitution and laws of the United States, but is also treated fairly and humanely,” Garland said in a written statement. “That obligation has special force in capital cases.”

President Biden is the first sitting president to oppose capital punishment, although he was also part of the Obama administration, which sought the death penalty in the Tsarnaev case. But Biden’s public statements about the death penalty strongly suggested there would be such a moratorium in his administration — in stark contrast to the Trump administration, which aggressively restarted executions.

In the final months of the Trump administration, 13 federal inmates were put to death, after years without any federal executions. The federal government’s death penalty policies do not apply to death sentences issued in state courts, so Garland’s directive will not affect any state executions.

In the Tsarnaev case, a court vacated his death sentence but the Supreme Court said it would review the matter. In mid-June, Justice Department lawyers urged the court to reinstate the death penalty for Tsarnaev, calling his conduct “one of the worst” acts of terrorism on U.S. soil since the 9/11 attacks.

Now, Garland has ordered a review of whether the drug approved for federal executions, pentobarbital, poses risks of pain and suffering. Garland’s review also will examine a decision made late last year to allow other methods of execution besides lethal injection, including electrocution and firing squad, and allowed for executions to take place in state facilities rather than federal prisons.

Officials said no federal executions will be scheduled while those reviews are conducted.

Garland’s decision comes amid criticism from some Democrats who say he has not moved fast or far enough to undo decisions made at the Justice Department during the Trump years.

In 2020, when Trump’s Justice Department began scheduling executions again, then-Attorney General William P. Barr said the American people had chosen, by electing members of Congress and presidents who supported the death penalty, to apply the death penalty for those “convicted of the most heinous crimes. . . . We owe it to the victims of these horrific crimes, and to the families left behind, to carry forward the sentence imposed by our justice system.”

Death penalty opponents who had condemned Barr’s actions cheered Garland’s moratorium.

Ruth Friedman, director of the Federal Capital Habeas Project, called it a “step in the right direction, but it is not enough.” She urged the Biden administration to commute all federal death sentences because the system is “marred by racial bias, arbitrariness, over-reaching, and grievous mistakes by defense lawyers and prosecutors that make it broken beyond repair.”

NAACP President Derrick Johnson called the death penalty “one example of America’s unjust justice system. We are encouraged by the Attorney General’s announcement today to halt federal executions.”