Sean Ellis spent 21 years, seven months and 29 days imprisoned for a crime he has always said he did not commit.
In October 1993, the then 19-year-old black man was arrested for the murder of a white police officer.
The conviction and eventual exoneration of Sean Ellis is the subject of new Netflix true crime documentary, Trial 4, which is an eight-part series. The docuseries comes amid a year when the racial biases of the American criminal justice system are being exposed and examined thanks to the 'Black Lives Matter' movement, which erupted this year after George Floyd, an unarmed black man, was killed by a white police officer in Minneapolis.
Watch the trailer for Netflix's Trial 4 below. Post continues after video.
Here's what happened to Sean Ellis, and what he is doing now.
What happened to Sean Ellis?
On the night of the killing, police officer John Mulligan was asleep in his car outside a Walgreens store when he was shot five times in the face. The police officer's service weapon was missing and the driver's side door was unlocked.
At 3.49am on September 26, 1993, an employee at the Walgreens in Boston, Massachusetts, called 911. A police force of 65 detectives was subsequently formed to investigate the killing of Mulligan.
Six days after the murder, Ellis' cousins – Celine Kirk and Tracy Brown – were murdered in their Boston apartment. While going through their apartment, detectives found Ellis' identification card, as he lived in the apartment with Brown. The police officers interviewed Ellis about his cousins' death, and during their interview Ellis mentioned he and a friend, Terry Patterson, went to Walgreens to purchase nappies on the night of Mulligan's murder.