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Convicted Cop Killer Gets New Trial in Boston Detective's Death

A Suffolk Superior Court judge has delivered a stinging rebuke to the leaders of Boston's law enforcement community who oversaw the 1993 murder investigation of Detective John J. Mulligan, ruling the investigation was tainted by corrupt detectives and marred by prosecutorial failures.

May 7, 2015
Convicted Cop Killer Gets New Trial in Boston Detective's Death

Boston Det. John J. Mulligan was shot and killed in 1993.

2 min to read


A Suffolk Superior Court judge has delivered a stinging rebuke to the leaders of Boston's law enforcement community who oversaw the 1993 murder investigation of Detective John J. Mulligan, ruling the investigation was tainted by corrupt detectives and marred by prosecutorial failures, reports the Boston Globe.

In a 67-page decision on Tuesday, Judge Carol S. Ball ordered a new trial for Sean Ellis, 40, who was convicted in 1995 after two mistrials of first-degree murder for the Sept. 26, 1993 shooting of Mulligan, stating that the prosecution was in a "rush to judgment." Ellis is serving a sentence of life without the possibility of parole.

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But Ball concluded that in the conviction of Ellis, "justice may not have been done'' and said defense attorney Rosemary Scapicchio has unearthed new evidence that "suggests there was corruption within the investigation of Mulligan's homicide itself.''

In 2000, Ellis’s co-defendant, Terry Patterson, who was convicted in a separate trial as the person who shot Mulligan, had his conviction vacated and the fingerprint evidence linking him to the crime was discredited. Patterson eventually pleaded guilty to manslaughter and was released from prison in 2007.

A spokesman for Suffolk District Attorney Daniel F. Conley, whose office inherited the case from a predecessor and also argued against Ellis getting a new trial, disputed Ball's findings, saying there's "not one single piece of evidence mentioned in this decision" that "contradicts the strong evidence that proved Ellis' guilt at trial."

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