A federal appeals court on Tuesday temporarily blocked a district judge’s decision to release Albert Woodfox, the last of the “Angola 3” prisoners still incarcerated after decades in solitary confinement.

Woodfox will remain at the West Feliciana jail until at least Friday while the 5th U.S. Circuit Court of Appeals considers the state’s request to halt his release.

The turn of events marks a new chapter for the prisoner who has served the United States’ longest stint ever in solitary confinement. Over the years, Woodfox has become a key symbol in the increasing wave of scrutiny of a prison practice opponents criticize as “cruel and unusual punishment.”

The U.S. Senate in 2012 convened a review of solitary confinement, a step one of Woodfox’s lawyers, Nicholas Trenticosta, says his client helped set in motion after his murder conviction was overturned for the second time in 2008.

Woodfox, along with former inmate Herman Wallace, is accused of killing Angola prison guard Brent Miller in 1972. Woodfox was convicted of the murder in 1973 and again in 1998, but both verdicts were reversed by the federal courts.

Aaron Sadler, communications director for the Louisiana Department of Justice, said in a statement that Woodfox belongs in prison “for the sake of the families of his victims and the multiple juries and grand juries that independently determined that this inmate should be held accountable for his multiple crimes.”

The inmate is “a twice-convicted murderer with an extensive criminal history,” Sadler noted.

But George Kendall, one of Woodfox’s attorneys, praised the Monday ruling by U.S. District Judge James Brady that said the prisoner should be freed.

“It undermines faith in the rule of law and in justice to see the state continue to pursue Mr. Woodfox’s incarceration under the harshest possible circumstances, especially after the state has been unable to secure a constitutionally sound conviction after two different chances,” Kendall and co-counsel Carine Williams said in a statement. “Mr. Woodfox is an elderly man in failing health who has been a model prisoner. We believe the 5th Circuit will find that the district court’s ruling was sound, well-reasoned, and based on well-established law.”

Outside the jail in St. Francisville where Woodfox is locked up, Kendall said Tuesday it would be virtually impossible for the state to provide a fair trial in the case because “nearly all the critical witnesses are dead.”

Kendall said it’s time for the case to end. He described his client as “guardedly hopeful,” saying Woodfox has seen victory and defeat in court in the past.

The state’s appeal with the 5th Circuit on Tuesday was filed under seal so that prosecutors could use documents that were sealed by Brady in the district court proceedings. Those documents, sealed at Woodfox’s request, according to an attorney general’s motion, include information about “criminal history, disciplinary records and financial statements.”

Woodfox had been moved to the West Feliciana jail to await a third trial in Miller’s stabbing death. That retrial was also blocked by Brady in his Monday ruling, an extraordinary move that the judge said was based on a variety of factors, from the 68-year-old inmate’s poor health to his unusually long stint in solitary confinement.

Woodfox’s unanimous 1973 and 1988 murder convictions were overturned because of problems with the handling of the grand juries that indicted him on murder charges. Brady overturned the second murder conviction in 2013 because of racial discrimination in the selection of the grand jury foreman.

The longtime state inmate was indicted once again in Miller’s death on Feb. 12 by a state grand jury.

Woodfox arrived at the Louisiana State Penitentiary at Angola in the early 1970s, after his conviction in New Orleans on an armed robbery charge.

Both Woodfox and Herman Wallace, who was accused of helping kill Miller, have argued they were falsely blamed for the prison guard’s death because they were once organizers for a Black Panther Party group within the prison. In the early 1970s, they were among a group of inmates who sought to expose brutal conditions at Angola, which had earned a reputation as being one of the worst prisons in the country.

Along with Robert King Wilkerson, they became known as the “Angola 3,” one-time Black Panthers who together served exceptionally long stints on a solitary tier. Woodfox and Wallace were assigned to solitary the day after Miller’s death, according to a lawsuit.

Louisiana Department of Corrections officials have repeatedly defended their policies for “closed cell restriction,” the term they use for what courts have ruled is effectively solitary. In the case of another longtime inmate on the tier, a DOC spokeswoman recently said the unit is a “non-punitive housing area” and the assignment is regularly reviewed by prison officials.

Wallace was released from prison in October 2013 but died days later. Wilkerson was released from Angola in 2001.

Along with the other Angola 3 members, Woodfox had sued the state of Louisiana about the conditions of his confinement. But he had largely remained in solitary for more than 40 years.

In recent months, that hasn’t been the case. Erin Foster, a spokeswoman for the West Feliciana Sheriff’s Office, said Woodfox has been held in the West Feliciana Detention Center since late February. He is being held in the general prison population, she said, and has never been placed in solitary confinement while at the parish jail.

* This story was edited after publication to correct the date of Woodfox’s second trial.