Former death row inmates who had their sentences commuted by former President Joe Biden are suing the Trump administration over its plans to send them to a supermax prison.

President Donald Trump has slammed Biden's decision to commute 37 federal death sentences to life in prison without parole on numerous occasions. A commutation allowed the death row inmates to avoid execution but they are instead serving life sentences.

Trump ordered earlier this year that the prisoners be held “in conditions consistent with the monstrosity of their crimes and the threats they pose.”

Twenty-one of the prisoners said in Wednesday's court filings that following Trump’s order, they were heading to the ADX prison in Florence , Colorado, where they would face “the most oppressive conditions in the entire federal prison system,” according to The Washington Post .

According to the Federal Bureau of Prisons , ADX is “a unique facility designed to house inmates who pose the greatest risks to staff, other inmates, and the public.”

The inmates argued that they’re being sent to the remote, isolating prison because of Biden’s actions.

The lawsuit was filed in the U.S. District Court for the District of Columbia and argued that the prisoners are concerned that they may be moved from an Indiana federal facility next week. If the plan continues, the death row inmates would move to Colorado at the famed prison that was home to Oklahoma City bomber Timothy McVeigh, “Unabomber” Theodore Kaczynski and ‘shoe bomber” Richard Reid.

On Thursday night, the Department of Justice said in a filing that they had made “no final decision” regarding any of the inmates, adding that no one would be moved until at least May 16.

“They feel devastated,” Brian Stull, a lawyer for the inmates, told The Post.

“Nobody’s looking at how well they did in prison, or their rehabilitation,” Stull added. He’s the deputy director of the American Civil Liberties Union ’s Capital Punishment Project.

“They’re just assuming they are the worst of the worst by virtue of their death sentences,” the attorney argued.

Stull said the death sentences were linked to a number of issues, such as whether the inmate had faced aggressive prosecutors or if they had inadequate legal representation. He noted that the crimes were similar to many of those that resulted in life sentences, such as those reached via plea agreements or because prosecutors chose not to seek the death penalty .

“We have some very medically fragile clients,” said Stull. “We do not know if all of our clients can survive this transfer.”

Trump has vociferously backed the use of the death penalty, and his administration has committed to seeking more death sentences.

During Trump’s first stint in the White House , the Department of Justice conducted 13 federal executions. Even as Biden campaigned against the death penalty and his administration halted federal executions, they also defended existing death sentences and sought additional ones.

In December, Biden commuted the death sentences of all but three inmates on federal death row. Those whose death sentences remained in place include the surviving Boston Marathon bomber and the gunmen who perpetrated shootings at a church in Charleston , South Carolina , and a synagogue in Pittsburgh . They were all sentenced when Biden was either president or vice president.

The use of the death penalty has significantly decreased in the last few decades, with both new death sentences and executions declining. The Post found last year that many of the 2,000 inmates on death row are likely to die without being executed. Most death row inmates are held at the state level, not by the federal government.

The Department of Justice has recently begun discussing taking action to seek new federal death sentences, with Attorney General Pam Bondi announcing that she was directing New York prosecutors to seek the death penalty for Luigi Mangione , who stands accused of having killed a health insurance executive last year.

The inmates’ lawsuit accused Bondi and the Associate Deputy Attorney General, Emil Bove, of not following regular processes to have them transferred.

The legal filing alleged that “sham” hearings were held to find that the prisoners must be sent to the supermax prison, arguing that the actions were “vindictive.”