The woman, whose testimony is to continue Thursday, was allowed to testify despite her refusal to discuss alleged welfare fraud — an issue on which the defense had hoped to attack her credibility. She invoked the Fifth Amendment in fending off that line of questioning.
Looking directly at the jury during a convoluted and sometimes tearful account, the woman once punctuated her words by snapping her fingers and later affected the German accent of a Jackson associate. She addressed news reporters directly at one point, and at other times glanced at Jackson, who sat motionless at the defense table.
Jackson, 46, is accused of molesting a 13-year-old former cancer patient, plying the boy with alcohol, and holding his family captive in February and March 2003 to get them to help rebut a damaging documentary.
The accuser's mother said following the broadcast of the documentary showing Jackson and her children, the pop star convinced her that her children were in danger, that there were "killers" after them, and that he was the only one who could protect them.
"I thought, 'What a nice guy,"' she said. "I was just like a sponge, believing him, trusting him." She recounted what she sarcastically called Jackson's "lovey dovey speech" at a Florida hotel room, in which Jackson told the family "in a very male voice" that he would be their father figure and protector.
She said Jackson told the family "that he loves us, that he cares about us, we're family. ... That we were in the back of the line, now we're in the front of the line, that he's going to protect us from those killers."
Later she added: "And you know what? They ended up being the killers."
Asked by Senior Deputy District Attorney Ron Zonen about her memory of the events, she pointed to her head and exclaimed: "Some things are just burned in here."
She then offered an account, in conflict with testimony of other witnesses, in which she described seeing Jackson lick her son's head during a February 2003 flight from Miami to California on a private jet.
"Everyone was asleep. I had not slept for so long," she said. "I got up. I figured this was my chance to figure out what was going on back there. And that's when I saw Michael licking (the boy's) head."
She sobbed, pounded her chest and said, "I thought I was seeing things. I thought it was me."
During more than four hours of testimony, defense attorney Thomas Mesereau Jr. did not make a single objection. The woman was to return to the stand Thursday.
CBS News Legal Analyst Andrew Cohen says she is the second or third most important witness for the case, only after her son.
"For prosecutors, she is at the heart of the conspiracy charge against Jackson," Cohen said. "For the defense, she is at the heart of a broad extortion attempt against their client. If the jury likes her and thinks she is credible, it's a big win for prosecutors. If not, advantage Jackson."
Before court recessed, Zonen played tape-recorded phone conversations between the woman and Jackson aide Frank Tyson, an unindicted co-conspirator.
"Let us take care of you. Let us protect you," he is heard saying. "Trust me. ... Now is not the time to be out there alone."
"I thought he was a good guy," the woman said of Tyson, "and he ended up being the worst of all of them."
She said she eventually returned to Jackson's Neverland ranch, gave an interview to a private investigator and appeared on a rebuttal video in which she lavishly praised Jackson. "Everything I said, I said it with my heart," she said.
In the February 2003 documentary, Jackson had said he let children sleep in his bed but characterized it as innocent.
Earlier, the woman described how she had lived from 1998 to 2003 in a small bachelor-style apartment with only one main room. She said her son and husband sometimes stayed at her mother's house because the boy had a special sterile room there.
Defense attorneys contend the family kept the bachelor apartment to make celebrities believe they were poor, but actually spent much of their time at the home of the boy's grandmother.
They also have raised questions about the woman's credibility by accusing her of bilking celebrities and committing welfare fraud. District Attorney Thomas Sneddon said in opening statements the woman would admit she took welfare payments to which she wasn't entitled.
But in taking the stand outside the presence of jurors earlier in the day, the woman took the Fifth, and refused to discuss "everything to do with the welfare application."
Melville allowed her to testify, despite vehement arguments from defense attorney Robert Sanger. The judge rejected a request for a mistrial, saying the defense could raise questions about the woman's credibility through other testimony.