DA says MGH shooting ‘justified’

Paul Langone, an off-duty security officer carrying a concealed handgun, may have been her only chance, authorities said yesterday.

Providing new details about Tuesday’s savage attack at a Massachusetts General Hospital psychiatric clinic, prosecutors said Langone’s fatal shooting of Jay Carciero, a 37-year-old in treatment for bipolar disorder, was legally justified.

He almost surely saved Desrosiers’ life, they said, and possibly the lives of others in the vicinity.

Speaking at an afternoon press conference in Cambridge, Suffolk District Attorney Daniel F. Conley said all evidence, including witness accounts and Langone’s statements to police, indicated that Langone acted lawfully in killing Carciero, a married father of four young children who had long struggled with mental illness before turning a knife on his therapist.

Authorities’ findings undercut accusations by Carciero’s attorney that Langone had acted rashly in using deadly force. Langone, a 33-year-old former boxing standout who has worked as a doorman at Boston bars, has been widely hailed for his unhesitating bravery in rescuing Desrosiers, a 49-year-old psychiatrist from Belmont.

Desrosiers has not been interviewed by police yet because of her injuries. She is expected to survive, but remains in serious condition.

When police arrived, Langone identified himself as the shooter, surrendered his gun, and submitted to a lengthy interview by investigators. He was then released from custody and has not been charged with any crime.

Because Carciero and Langone live just 2 miles apart in Reading, investigators explored potential connections between the men, but found none, Conley said. Family members had previously said the men did not know each other.

Langone was at a scheduled appointment on the fifth floor of the high-rise office building when the attack occurred, Conley said. Besides the Bipolar Clinic and Research Program, the floor contains several other medical and research offices, Conley said, declining to be more specific.

Conley emphasized that the investigation is in its preliminary stages and will remain active until a final decision on criminal charges is made.

Langone was authorized to carry a weapon in his capacity as a sworn special police officer, a title given to security personnel who work for private firms but are licensed by Boston police.

When Langone stormed into the room, he saw Carciero on top of Desrosiers, prosecutors said yesterday. He instructed Carciero to drop his weapon, a folding knife he brought to the session, but Carciero refused and may have made threatening motions in Langone’s direction.

Langone then fired multiple shots, striking him twice, once in the torso and once in the head, according to two law enforcement officials with knowledge of the case.

After officers removed his gun, several hospital workers embraced Langone in gratitude, said two law enforcement officials who spoke on the condition they would not be named.

Security at the Staniford Street building is light and does not include metal detectors.

Police did not discuss potential motives for the knife attack. Carciero had no history of violence, according to his lawyer.

Carciero had a minor criminal record, authorities said. In April 2007, he was arraigned on charges of disorderly conduct, refusing to identify himself during a motor vehicle stop, and giving a false address to police. He was placed on probation and the charges were later dismissed.

Paul Langone, who hopes to become a police officer, has not spoken publicly since the attack, but his father has praised his actions in coming to a stranger’s defense at risk of personal harm. He said yesterday that he remained confident his son would be “completely exonerated’’ from any fault.

“It is impossible for a father to be more proud of his son than I am,’’ he told WHDH-TV shortly after the press conference.

He said the family would continue to pray for the Carcieros and is deeply saddened by their loss.

As she left her Reading home yesterday for a midday Mass, Langone’s mother said her son “doesn’t feel like a hero.’’

“Anyone else would do the same thing under the same circumstances,’’ she said, declining to give reporters her name. “We’re very proud of him. He’s a remarkable young man, and he always has been.’’

“There are two Reading families in a very unique and delicate situation,’’ she continued. “Out of respect for the other family, I’m not going to say anything.’’

James Perullo, a Boston lawyer speaking on behalf of the Carciero family, questioned why Langone shot Carciero multiple times, calling the action rash. He said he had been told that Langone had already disabled Carciero when he fired the fatal shot.

“I can appreciate that Jay is someone who may have needed to be shot in that environment,’’ said Perullo, stressing that he was speaking for himself and not the Carciero family.

“Philosophically, I have problems with it,’’ he said, “but I can accept the concept.’’

Perullo declined to comment on whether the family is considering a wrongful death lawsuit against Langone.

Carciero’s family issued a statement yesterday saying that he was a gentle and caring person and that what occurred Tuesday “remains unexplainable to us,’’ the Associated Press reported.

The family expressed its thoughts and prayers for the recovery of Desrosiers and said it was establishing a trust fund for Carciero’s children through the Stoneham Municipal Federal Credit Union, according to AP.

Brian Ballou of the Globe staff contributed to this report.