But as her lawyers paint the picture of an abused wife who acted in self-defense, Crespo's brother tells a different story. He spoke exclusively with Eyewitness News on Thursday, revealing a secret affair between Daniel Crespo and another woman.
"He came to me crying and he said, 'Willy I cheated on her,'" said William Crespo, Daniel Crespo's brother. "It was wrong that he cheated on her."
William Crespo says Daniel had a mistress, an affair that he was ashamed of and tried to break off. But the woman was persistent, says William, even telling Daniel that she was carrying his baby.
"She wouldn't let go. She kept saying she was pregnant, and then my brother, he wanted to find out if she was really pregnant. She was pregnant," said William. "She was. She's not pregnant. She lost the baby."
William says he and his brother have always been close, and that Daniel confessed a year ago that he was having the affair with the woman, whom Eyewitness News is not identifying.
William says she harassed both Daniel and his wife Lyvette. William heard the woman calling the morning of the shooting, when Lyvette was present.
When asked if Lyvette got mad, William said, "Yes. What wife wouldn't get mad?"
William Crespo believes the woman called later too, igniting a final fight between the couple, ending when Lyvette fired the fatal shots.
"I seen the phone and I seen the woman. She was at the hospital when he died," said William. "She said, 'Oh I just talked to him a little while ago.'"
The lead homicide detective in the case tells Eyewitness News that William Crespo's information is an element of their investigation, but will not say whether Lyvette disclosed anything about an alleged affair during questioning.
Thursday, attorneys for the family say there was only one motive: that Lyvette shot in self-defense.
"I think the evidence will corroborate that she's been the victim of domestic violence for many years," said Eber Bayona, Lyvette Crespo's attorney.
Investigators say they have no record of any disturbances at the home. The wife's attorney says they suffered in silence.
"They are entrapped in these situations and sometimes it's not easy for them to go and tell somebody," said Bayona.
William Crespo says his brother was not an abuser. He says it is important for people to know there was much more stressing out the marriage that had lasted 28 years.
"Lyvette don't have a husband and she don't have to bother no more, and my brother could rest at peace," said William. "That's what I want, him to rest in peace. Nothing's going to bring him back."
The lead detective tells Eyewitness News there is much more to go in the investigation, and that it could take one or two more weeks before they turn the case over to the District Attorney to determine whether Lyvette Crespo should be criminally charged.