Bill Cosby’s former co-star has sparked outrage with her jubilant reaction to his sexual assault conviction being overturned.

Cosby walked free from jail on Wednesday (US time) just two hours after his 10-year sentence was overturned by the Pennsylvania Supreme Court.

“FINALLY!!!! A terrible wrong is being righted – a miscarriage of justice is corrected!” Cosby Show star Phylicia Rashad tweeted in the aftermath, sharing a photo of her former co-star.

The Supreme Court issued its 4-3 split decision after the 83-year-old Cosby had served more than two years of his sentence following his 2018 conviction.

He was found guilty of drugging and molesting Andrea Constand, an employee at his alma mater Temple University, at his home in 2004. Ms Constand’s allegations were the only ones against Cosby that were not too old to allow for criminal charges.

But the court said he should never have faced charges after striking a non-prosecution deal with a previous district attorney more than 15 years ago.

Montgomery County District Attorney Kevin Steele, who charged Cosby in 2015, noted that a jury found him guilty and the Supreme Court’s decision was not based on the facts of the case.

Cosby was released from a state prison in Pennsylvania just before 2.30pm (4.30am on Thursday AEST). About an hour later, he arrived at his mansion in Elkins Park, a Philadelphia suburb, before making a brief appearance alongside his lawyers in front of the media.

A frail-looking Cosby smiled and nodded when asked if he was happy to be home, but he did not answer questions.

Later, he posted a statement to on Twitter, thanking his supporters and saying: “I have never changed my stance nor my story. I have always maintained my innocence.”

Cosby is best known for his role as the loveable husband and father in the 1980s television comedy series The Cosby Show, earning him the nickname “America’s dad”.

His family-friendly reputation was shattered after dozens of women accused him of sexual assault over a period of decades. His conviction was widely seen as a watershed moment in the #MeToo movement that brought forth an array of allegations against powerful men in Hollywood and beyond.

Tweet from @aliciasanchez

Rashad, who played Cosby’s wife, Clair Huxtable, on the show, was forced to explain her support for her former co-star after it sparked outrage.

“I fully support survivors of sexual assault coming forward. My post was in no way intended to be insensitive to their truth,” she tweeted later.

“Personally, I know from friends and family that such abuse has lifelong residual effects. My heartfelt wish is for healing.”

Rashad, who was recently named dean of Howard University’s Fine Arts department, has supported the disgraced comedian since he was charged for drugging and molesting Ms Constand in 2004.

“Phylicia has never wavered in her support of Bill and she’s said she’ll be available for whatever he might need, whenever he might need it,” a source close to the actress told Page Six in 2017.

Many women involved in the #MeToo movement have expressed horror at the Supreme Court decision.

“THIS is why women do not come forward,” writer E Jean Carroll, who has accused former US president Donald Trump of raping her in the 1990s, wrote on Twitter. Mr Trump has denied her claim.

Lisa Bloom, a lawyer who represented some of Cosby’s accusers, told CNN she was “absolutely disgusted and shocked”.

In a statement, Ms Constand and her lawyers said they were disappointed in the ruling and concerned it could dissuade other victims from seeking justice.

“Once again, we remain grateful to those women who came forward to tell their stories,” they said.

-with AAP