The lead investigator in the Michael Jackson (search) case testified Wednesday that the young accuser slumped down in his seat and became "choked up" when first interviewed about allegedly being molested by the pop star.

Sheriff's Sgt. Steve Robel also testified that the boy told him he was molested five to seven times, but could not recall what happened every time.

"He was fine with talking to us," Robel said of the teenage boy's initial interview. "When I got into the molestation acts I noticed a change in (his) demeanor. He became very quiet, folded his arms and sank down into his chair. ... He even became choked up."

Robel's questioning by District Attorney Tom Sneddon (search) and cross-examination by Jackson attorney Robert Sanger also delved into differences in the number of alleged molestation incidents that have emerged in testimony.

The boy himself testified in the trial to only two molestations but said he believed there may have been more. Despite the statements about five to seven incidents, the investigator said that since the first interviews of the boy in July 2003 he has been able to provide detailed accounts of only two alleged molestations.

The possibility of the accuser not being aware or fully aware at certain times has been raised in testimony by the boy's brother, who said he twice witnessed his brother being molested while asleep.

Jackson, 46, is accused of molesting the boy, giving him alcohol and conspiring to hold the boy's family captive to get them to rebut a TV documentary in which Jackson appeared with the boy and said he let children sleep in his bed but it was non-sexual and innocent.

The defense denies that any molestations occurred and has depicted the accuser as a vengeful child who made up the stories after he and his family were evicted from Jackson's Neverland (search) ranch.

Before court recessed, Judge Rodney Melville (search) said he plans to hold a hearing next week on whether prosecutors can present evidence of allegations against Jackson in 1993 by a boy who claimed he was molested. No charges were filed and that case was settled out of court for more than $20 million.

The prosecution wants to invoke a legal provision which allows using similar past actions against a defendant. The judge said at the trial's outset he would not consider the matter until after the prosecution presented its molestation evidence in the current case. He gave the defense until Friday to file its final papers opposing use of such evidence.

The bulk of Wednesday's trial session was devoted to prosecutors' X-rated video presentation of adult materials seized during a November 2003 raid on Jackson's estate. Huge enlargements of magazine covers showing topless women in suggestive poses were flashed before the jury.

But several times the defense pointed out that the magazines had publication dates months after the accusing family had left Neverland. Law enforcement witnesses offered no evidence that the accuser saw the items and said the items were legal and commercially available.

Mesereau said in his opening statement that Jackson would admit that he reads "girlie magazines" but never showed them to children.

The defense also cross-examined Robel about what he knew of the rebuttal video, in which the family praised Jackson as a father figure.

Robel testified that before obtaining an arrest warrant for Jackson, none of the investigators had seen the rebuttal video.

"And it did not appear to you to be consistent with what you had been hearing from the family?" Sanger asked.

"I was not alarmed," said Robel, "because I recalled what (the mother) said to me in her initial interview."

Robel said the mother indicated she was instructed by a Jackson associate to do the video.