Judge Ends Prosecution Against Sean Ellis For Killing Of Boston Police Detective

BOSTON (CBS) - It was a moment 25 years in the making. After a brief motion to dismiss charges and an elevator ride down to the Suffolk County Probation Department, a Suffolk Superior Court judge formally ended the prosecution of Sean Ellis and he was set free Tuesday.

"It's everything I expected and more. I'm fortunate to be able to see my mom," said Ellis outside courtroom 906.

The 44-year-old served more than 22 years in prison for the killing of Boston Police Detective John Mulligan. But his murder conviction was overturned in 2015 after the state's highest court found corrupt detectives handled the homicide investigation.

Then Monday, the Commonwealth announced it would drop the case against Ellis; ten months ahead of what would've been the start of his fourth trial.

"I've determined that the evidence we could reasonably expect to introduce is no longer sufficient to achieve a conviction," said Suffolk County Acting District Attorney John Pappas.

For his family, who has long maintained Ellis' innocence, Tuesday marked the start of a new life.

"Every single day I said 'Lord, I know I've prayed for this before but I'm praying for it again. Please bring my son home and he did,'" said Mary Ellis, Sean's mom.

Sharday Taylor, Sean's sister, says she's looking forward to spending the holidays as a family. "I was three years old that was the last time I knew him, to be him, a completely free man. Now today, at 28 I get to see my brother again completely free."

Ellis say he now plans to enroll in college.