An abusive husband strangled his estranged wife to death in her Chelsea home just two days after she told him that she was filing divorce papers to officially end their relationship, a Suffolk County prosecutor told a Superior Court jury today in the defendant’s second trial for Alicia Lao’s murder.

“The person who strangled her and left her to die was the ex-husband she tried to get away from … the defendant, AGAPITO LAO,” said Assistant District Attorney Mark Lee, deputy chief of the district attorney’s Homicide Unit.

Lao (D.O.B. 7/10/58) is charged with first-degree murder for the May 2, 2000, homicide of 40-year-old Alicia Lao, who was found asphyxiated and stabbed on a bed they once shared in an apartment on Bellingham Street. Lao was found guilty of that offense after a 2002 trial, but his conviction was overturned in 2007 by the Supreme Judicial Court.

Lee told jurors today that Agapito and Alicia Lao married in Puerto Rico in 1979 before moving to Massachusetts and settling into a Chelsea triple-decker. During the course of their relationship, they had three children together but their marriage was marred by the defendant’s “violence and controlling behavior.”

Lee said the defendant would not abuse his wife in public. Instead, Alicia’s daughter would wake up in the morning to find her mother’s face and eyes bruised, he said. Lee described the “rules” that Alicia was expected to follow, including paging and checking in with Lao constantly.

“She couldn’t do a thing without having to check in with him,” Lee said. Eventually, Alicia even lost contact with her family, and stopped having visitors over to her home.

Alicia’s situation started to change in 1997, when she was a patient at Massachusetts General Hospital, Lee said. During a medical visit, she met and struck up a fast friendship with a custodian who worked in the hospital. The two exchanged phone numbers and began having telephone conversations. The relationship eventually turned romantic.

At the time, Alicia was separating from her husband but the two were still legally married.

Alicia’s and her new romantic interest ended their relationship and the man moved to New York City in 1999. They continued to be friends, and she occasionally visited him on the weekends with her children. In 2000, the two made the choice to live together, Lee said, and on April 30 of that year, Alicia went to see the defendant to tell him that she would be filing divorce papers with the court, and that her boyfriend would be moving into the Bellingham Street home the next day to live with her and the children.

“When the defendant dropped Alicia off, he tried to hit her with his car,” Lee said. Alicia reported the incident to the Chelsea Police Department.

On May 1, Alicia’s boyfriend packed two suitcases and took a bus from New York City to Boston, arriving at her home that evening.

Lee told the court that on the morning of May 2, Alicia’s children had gotten up and were leaving for school at about the same time that her boyfriend was getting ready to leave the house. When he left, she was the only one home.

Sometime between 8:50 and 10:15 that morning, when she was discovered motionless on her bed by her boyfriend, “the defendant strangled Alicia in her room,” Lee said. An upstairs neighbor later told investigators that she “heard banging and pounding, followed by horrible screams of a female.” That neighbor “went to her back door, and cracked it open and saw the defendant” as he exited the apartment, Lee told jurors.

Another witness who was outside fixing a car, and who knew the defendant well, allegedly saw him coming out of the apartment.

“He had known the defendant for years,” Lee said. “It was broad daylight. He had no reason to mistake who that was who got into that van.”

“The evidence will show the circumstances, the timing and the personal observations of people on Bellingham Street, and it will be unmistakable in your mind who did this and how he did it,” Lee told jurors.

It was Alicia’s boyfriend who found her upon returning home from a job interview.

“Nothing could have prepared him for what he saw when he walked into the master bedroom,” Lee said. “Alicia was on the bed, her legs dangling off the side, in a pool of blood with blood on the pillow, a telephone receiver in her hand and marks around her neck,” Lee said.

Though Alicia Lao remained physically alive, her brain was dead, Lee said, and she was taken off life support on May 17.

“This is a case about a man with a history of domestic violence, being seen in a place where he didn’t belong, where he was no longer living,” Lee said. “The individual responsible for Alicia Lao’s death and the loss to her family is the defendant.”

Agapito Lao is represented by attorney Gary Schubert. Testimony is ongoing before Superior Court Judge Charles Spurlock in courtroom 808.