US prison
A guard stands behind bars at the Adjustment Center of a US prison. - Representational image Reuters

A woman has been freed from prison after spending 23 years inside for a crime she never committed.

Tyra Patterson was sentenced to prison in 1994 for being an accomplice to murder after witnessing her friend kill another person.

On Christmas Day, at the age of 42, Patterson was released and reunited with her family.

Celebrities joined a wider campaign calling for her release after she was jailed under an Ohio law which means that an accomplice can be given the same sentence as a killer.

After being released, she hugged her family and friends shouting "let's eat and open gifts".

Celebrities joined the campaign for her release and they included the actress Alfre Woodard, Mad Men creator Matthew Weiner and the filmmaker Ken Burns.

Patterson had been charged following the murder of 15-year-old Michelle Lai in Cleveland, Ohio, but always maintained her innocence. Lai's family were also involved in the calls to release her.

The victim's sister, Holly Lai, had been with Michelle on the night of the murder along with other members of a group of friends, burgling garages.

They came across Patterson in an alleyway and a scuffle ensued in which Michelle Lai was shot dead in the head. Another girl at the scene, LaShawna Keeney, is accused of firing the fatal shot.

Patterson first applied for parole back in 2011 but had the request denied before it was finally accepted in October 2017.