By Jon Keller

BOSTON (CBS) – Suffolk District Attorney Rachael Rollins said Sean Ellis’ case is “not over” and she will work to determine if he should be completely exonerated.

The 44-year-old Ellis 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.

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In 2018, a Suffolk Superior Court judge formally ended the prosecution of Sean Ellis and he was set free.

Ellis’ story gained publicity in recent weeks with the release of the Netflix documentary “Trial 4.”

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Rollins discussed Ellis’ case with WBZ-TV political analyst Jon Keller. She said she is following the case closely through court documents and other legal proceedings to make sure Ellis receives a fair final outcome.

“I am deeply invested in this case. I think it’s a brand on our city, and not a good one,” she said.

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Keller @ Large: Rachael Rollins On Sean Ellis

Jon Keller