Attorney General William Barr directed the Justice Department on Thursday to adopt a new rule for carrying out the death penalty, which would restore executions in the federal system for the first time in 16 years.

"We owe it to the victims and their families to carry forward the sentence imposed by our justice system," Barr said.

In response to the order, the Bureau of Prisons set execution dates for five men on federal death row who have exhausted their legal appeals, all of whom were convicted of murdering children in especially violent crimes. Four of the five also killed adult victims. Their executions are to be carried out in December and January.

"Under administrations of both parties, the Department of Justice has sought the death penalty against the worst criminals," Barr said. Additional executions will be scheduled at a later date, the department said in a statement.

Since the Supreme Court allowed the death penalty to resume in the mid-1970s, after an earlier ruling had declared its application unconstitutional, the federal government has executed only three inmates, including Timothy McVeigh, who bombed the Oklahoma City federal building in 1995. Legal challenges involving the system for using three drugs to carry out lethal injections led to court rulings that stopped federal executions in 2003.

The last federal execution occurred that year, when Louis Jones Jr. was put to death for raping and murdering a 19-year-old female soldier.

Barr's order directs the Bureau of Prisons to use a single drug, a powerful barbiturate called pentobarbital, in its lethal execution chamber at the federal prison in Terre Haute, Indiana. Three states — Georgia, Missouri and Texas — have also used that same drug to administer the death penalty.

After a botched state execution in Oklahoma, then-President Barack Obama directed the Justice Department to review the use of lethal injection drugs in 2014. Pharmaceutical companies that make drugs used by states for lethal injections have refused to make them available for that purpose, further complicating the task of carrying out executions.

Sixty inmates are currently on the federal death row, but many are still pursuing legal appeals, including convicted Boston Marathon bomber Dzhokhar Tsarnaev, convicted of setting off a bomb at the Boston Marathon in 2013. Dylann Roof, sentenced to death for killing nine black worshipers in June 2015 at the Emmanuel AME Church in Charleston, South Carolina, is also among the inmates on federal death row.

"This is counter to the national trend," said Robert Dunham of the Death Penalty Information Center, a group that opposes capital punishment. "The death penalty is disappearing from whole sections of the country and eroding in others."

Both the number of death sentences imposed by juries and executions remained near historic lows in 2018, as public support for capital punishment continued to decline. The latest Gallup poll showed 56 percent of Americans supporting the death penalty, down from a high of 80 percent in the mid-1990s.

"The question with this administration has been, was it going to follow the national pattern that we've seen or was it going to be an outlier," Dunham said.