Sylvester Mitchell’s wife “picked the wrong lie” when she told police she had nothing to do with his homicide, only to change her story later and claim she stabbed him in self-defense, a senior Suffolk County prosecutor said at the close of her trial today.

“She lied, because she knew she had done wrong,” said Assistant District Attorney David Deakin, chief of the Suffolk DA’s Family Protection and Sexual Assault Bureau. “She stabbed her husband and she knew she had been caught.”

SHARON FITZPATRICK (D.O.B. 7/26/71) is charged with second-degree murder for stabbing Mitchell to death in their Evans Street home at about 4:30 a.m. on his 40th birthday, May 5, 2007.

Arguing against her claim of self-defense, Deakin pointed out that Fitzpatrick was unwounded in the confrontation, while Mitchell suffered an “eviscerating stab wound to the abdomen and a fatal stab wound to the chest.” He held up photograph taken of the victim following the stabbing and said, “on his 40th birthday, Sylvester Mitchell wound up looking like this, and the defendant – his wife, Sharon Fitzpatrick – wound up looking exactly as she does sitting before you today.”

Deakin told the court that Fitzpatrick was angry when Mitchell came home early that morning because he had promised her that he would return home by midnight. She had cake and champagne ready for a private birthday celebration that never happened.

“Between 2:23 and 4:10 a.m., she called him nine times on his cell phone,” Deakin told the court. “She didn’t call him because she was worried. She called him because she was mad.”

Sometime prior to his arrival, Fitzpatrick used the door’s chain lock to lock Mitchell out. Mitchell forced the door open, and it was after he entered the house that the couple began to argue.

Deakin told the court that the defendant was never injured during their exchange and that, although she worked as a Boston Police 911 call operator, “there was no cry for help, no call to 911.”

Deakin told jurors that there were many opportunities for her to yell for assistance or make a phone call if she felt her life was in danger. Her brother-in-law lived in the apartment downstairs, there was a cell phone in the room where the confrontation happened, and her teenage son was sleeping upstairs.

Authorities say Mitchell’s brother came upstairs after hearing a loud thud. He found Fitzpatrick leaning over Mitchell’s body with her hands on his wounds, and ran downstairs to call 911.

It was during that time that Fitzpatrick hid the knife, Deakin said, “behind a mirror and underneath some electrical cords” in the couple’s bedroom.

Boston Police officers arrived on the scene shortly after receiving the brother’s emergency call. Fitzpatrick “said nothing” until her still-conscious husband told officers that he had come home stabbed, the prosecutor said.

“What did she do?” Deakin asked. “She jumped on the lie.”

The lie, Deakin said “would easily be disproved” after police found the murder weapon in the bedroom with the victim’s blood on the blade and the defendant’s fingerprints on the blade near the handle.

Even during an interview conducted by homicide detectives at the police station, “she stuck with the lie,” the prosecutor said. “She told police over and over again … that she wasn’t acting in self-defense.”

Deakin said that at no point during the police interview did she indicate she was afraid of Mitchell before stabbing him.

“Domestic violence is an extremely serious problem – a blight upon our society,” Deakin said. “Nobody would even think of denying that domestic violence is a horrible problem in our society. That the victim had a violent past does not give her permission to stab him to death in anger.”

Deakin noted the lack of additional injuries on his body – such as defensive wounds on his hands – as evidence that the defendant “took him by surprise” when she stabbed him.

“She had no right to stab him to death in anger and kill him,” he continued. “Your verdict can, and must, hold her accountable.”

After closing arguments, Judge Stephen Neel instructed the jury on the relevant law. If jurors do not reach a unanimous verdict this afternoon, they will return to courtroom 907 tomorrow morning. Jennifer Sears is the victim-witness advocate assigned to the case. Fitzpatrick is represented by attorney Rosemary Scapicchio.