Albert Woodfox, who has been held in solitary confinement for more than 40 years, walked out of a Louisiana prison early this afternoon.

This comes after he pleaded no contest on Friday to manslaughter charges in the death of prison guard Brent Miller in 1972.

Woodfox was the last behind bars of three prisoners known as the Angola Three because of their long confinement in Louisiana's Angola prison.

Over the course of decades, Woodfox has consistently maintained his innocence. And his lawyer tells The Times-Picayune that "no contest" does not imply guilt.

"It means simply that (Woodfox) does not contest that the State would present evidence at a new trial from witnesses who said he committed this crime," lawyer George Kendall says.

Here's how Louisiana Attorney General Jeff Landry characterized the outcome:

"Albert Woodfox, by his own plea, stands convicted of the homicide of Brent Miller. In accordance with that plea, he was sentenced to 42 years of incarceration and given credit for time served. Additionally, he waived his rights to appeal this sentence."

The Times-Picayune posted a statement from Woodfox, which includes:

"Although I was looking forward to proving my innocence at a new trial, concerns about my health and my age have caused me to resolve this case now and obtain my release with this no-contest plea to lesser charges. I hope the events of today will bring closure to many."

Eve Troeh from member station WWNO reported for NPR last year that this case "became an international human rights issue." Eve says the Angola Three have long maintained "they were framed for the prison guard's murder as retaliation for involvement in the Black Panther movement."

It's that same reason that prison officials used as a defense for putting the men into solitary confinement: they said "their Black Panther activism would otherwise rile up inmates at the maximum-security prison farm in Angola," the Associated Press reports.

Herman Wallace, another one of the three, died just days after he was freed in 2013. The case of the third prisoner, Robert King, was overturned in 2001. As NPR reported in 2013, here's how King described the prison conditions:

" 'The cells were pretty bare, and they were maybe about ... 3 feet wide and about 6 feet long. It was almost like it was in a tomb, and there was a slab of concrete that you slept on,' King says. 'You ate three meals a day — you had two slices of bread each meal. During the wintertime, you froze, and during summertime, you were overheated. But in any event, you were starved.' "

Woodfox told reporters outside the prison that he planned to visit his mother's grave. She died while he was incarcerated.

And as the AP reports, when asked "whether he would have done anything differently back in 1972, Woodfox responded: 'When forces are beyond your control, there's not a lot you can do. Angola was a very horrible place at the time and everybody was just fighting to survive from day to day.'"

He has been twice convicted for the guard's killing, but both verdicts have been overturned. As the Times-Picayune reports, a "grand jury indicted him Feb. 12, 2015, for a third time in the decades-old murder."

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