DA will finally drop case against Sean Ellis for murder of a BPD detective in 1993

Suffolk County District Attorney John Pappas announced this afternoon his office will not seek to retry Sean Ellis - for what would be the fourth time - for the shooting death of Det. John Mulligan in a Roslindale parking lot on Sept. 26, 1993, because of the passage of time and because of possible corruption by the detectives assigned to the case would make it difficult to win the case.

Ellis was charged with being one of two men who shot Mulligan in the face five times as he slept in a detail cruiser outside a Walgreens on American Legion Highway. He spent 22 years in prison for Mulligan's death before being released in 2015 after his lawyer, Rosemary Scapicchio, found evidence that suggested Mulligan was part of a ring of corrupt Boston detectives who robbed drug dealers and that they might have framed Ellis to get attention off what they and Mulligan were up to, in part by withholding evidence forom Ellis's attorney at the time.

In 2016, the Supreme Judicial Court ordered a new trial for Ellis - overturning its own 2000 ruling denying him one - based on what Scapicchio found and said she would use in a retrial:

We did not know at that time that these detectives had been engaged with the victim in criminal acts of police misconduct as recently as seventeen days before the victim's murder. ... They, therefore, had a powerful incentive to prevent a prolonged or comprehensive investigation, and to discourage or thwart any investigation of leads that might reveal the victim's corrupt acts.

Following that ruling, the DA's office had initially said it would try Ellis again for first-degree murder, saying nothing had changed any of the evidence that initially lead to Ellis's conviction.

Pappas explained his decision today:

Two major factors contributed to this decision. The nature of the evidence has not changed in 25 years, but the strength of it has declined with time. Moreover, the involvement of three corrupt police detectives to varying degrees in the investigation has further compromised our ability to put the best possible case before a jury.

As the SJC noted two years ago, Mr. Ellis was near the scene of the crime moments before it was committed, he fled the scene in its aftermath, and he possessed the murder weapon in the days that followed. The most likely critical issue at a new trial, then, would not be whether Mr. Ellis was involved in Det. Mulligan's homicide, but rather the level of his involvement with his convicted co-defendant, Terry Patterson.

As some of you may recall, Mr. Ellis' defense at trial was that Mr. Patterson committed the murder and robbery alone, on his own initiative, while Mr. Ellis was buying diapers at 3:00 in the morning. He claimed to his family that Mr. Patterson gave him the murder weapon and Det. Mulligan's service weapon after he left the store, and that they left the scene together.

We would have to rebut those claims at a new trial, and establish the state of mind and degree of participation necessary for a murder conviction - either that he was the shooter or that he knowingly participated and shared the intent of the shooter.

But that evidence could come only from eyewitnesses, including those who identified Mr. Ellis as the man they saw crouching by Det. Mulligan's vehicle shortly before the murder. And those specific recollections have, understandably, faded over the decades. The circumstances under which they were made would be presented against a markedly different backdrop than back in 1995.

Finally, and significantly, there is the involvement of three corrupt police detectives to varying degrees in the investigation. As we all know, Detectives Kenneth Acerra, Walter Robinson, and John Brazil disgraced themselves and tarnished their badges in a wide variety of criminal conduct unrelated to this case - the extent of which was unknown to prosecutors or defense counsel in 1995.

Perhaps more than any other factor, their shameful conduct presents a major challenge to our ability to put a successful case to a new jury.

As the SJC concluded 18 years ago, there is no reliable evidence that Acerra, Robinson, or Brazil procured or produced false evidence in this case. Based on the facts and circumstances known to us, we don't believe Det. Mulligan was involved in their schemes. But a lawyer today would argue that he was involved, and that they had a motive to protect themselves and their criminal enterprise - even at the cost of fully investigating a fellow officer's homicide. Unfortunately, no matter how irrelevant their corruption might be to John Mulligan's murder, it is now inextricably intertwined with the investigation and critical witnesses in the case.