First, Dominique Jackson beat her boyfriend, Adolphus Jackson, over the head with a cast-iron skillet. Then, as he lay unconscious in his bed, she doused him with hot sauce, milk, shaving cream, bleach and insect spray and burned him with an iron.

He was, she would explain later, "hissing like the devil."

And then she left him. And went to church. And to the zoo.

When she returned that night to his apartment in the 2400 block of 17th Street NW, Adolphus Jackson, all 108 pounds of him, was barely alive. She had two other people with her, and she called 911, pretending that they had just found the injured man.

Adolphus Jackson, 45, was taken to a hospital, where he died the next day. He was killed, the medical examiner found, by the blow from the skillet and the internal bleeding that resulted.

Yesterday, as Dominique Jackson was sentenced to 16 years for manslaughter, she did nothing to explain the rage behind the October 2004 slaying.

Jackson, 32, told D.C. Superior Court Judge Judith E. Retchin that she had nothing to say. She had written to the judge that she was abused when she was growing up, and the judge acknowledged that she had had a hard life.

But Retchin found the crime to be "particularly awful" and "brutal" and granted the prosecution's request that she impose the recommended maximum under the court's voluntary sentencing guidelines.

"I don't know why you did what you did, but it is very disturbing," Retchin told Jackson. "And after you did this, you just left him there, and he bled to death."

The judge had been so disturbed by the killing, she said, that she initially questioned Jackson's mental competency.

Jackson does have mental health problems, and in seeking leniency, her attorney, Lloyd Nolan of the D.C. Public Defender Service, explained that "there was clearly an imbalance going on at that time."

Neither the judge nor the prosecutor, Assistant U.S. Attorney Thomas A. DiBiase, disputed the need for mental health treatment. But mental examinations did not find a basis to mount an insanity defense or to challenge the defendant's competency.

So in July, she pleaded guilty to a relatively common charge, with a very uncommon qualifier: voluntary manslaughter while armed (skillet).

Jackson, who was also known as Kia Kenard, had been dating Adolphus Jackson, whose nickname was Gi-Gi, the prosecutor said. She was staying at his apartment, and the two argued frequently, according to the government.

But none of the other clashes ended like the fight that took place early Oct. 17, 2004.

Afterward, Dominique Jackson said Adolphus Jackson was stealing from her to support a crack habit. But investigators found no evidence that he used crack, let alone that he was stealing from her.

It was a brutal attack, without provocation, DiBiase said.

Before Dominique Jackson was led away, Nolan asked the judge to recommend that she be imprisoned at the Carswell Federal Medical Center in Texas, which provides specialized medical and mental health services to female offenders.

The judge agreed.