Michael Jackson's (search) attorneys Thursday showed a judge videotapes of the search of the singer's Neverland Ranch to press their claim that law enforcement officials improperly took evidence while building their molestation case.

The defense, claiming authorities overstepped their bounds, wants to keep some items seized from Jackson's home and a private investigator's office from being admitted as evidence in the case, which is scheduled for trial Jan. 31.

In one scene videotaped by authorities, investigators walked around the ranch as carnival music from the property's amusement rides and exhibits played in the background.

At one point in the footage, investigators entered a library with shelves stocked with films. At another point, the officials entered a museum filled with costumed mannequins.

Defense attorney Robert Sanger (search) questioned Santa Barbara County sheriff's Sgt. Ross Ruth about why he entered an office that one ranch employee had identified as Jackson's.

Ruth testified he entered the office without believing it was the singer's. He said he did not believe the employee, a woman wearing a maid's uniform, because she gave evasive answers.

During the taped search, she flicked a light switch. No lights could be seen going on or off, and Ruth said he suspected she might have been activating cameras. Judge Rodney S. Melville struck that testimony from the record, saying it was speculative.

Jackson, 46, has pleaded not guilty to child molestation, conspiracy and administering an intoxicating agent, alcohol.

On Friday, the mother of the alleged molestation victim will take the stand to answer questions about whether she knew private investigator Bradley Miller was working for former Jackson attorney Mark Geragos (search) when Miller's office was searched.

Authorities say Jackson has indicated he will be in court when the boy's mother testifies.

Defense attorneys say the mother and prosecutors knew or should have known that Miller worked for Geragos and that his office should not have been searched because of the attorney-client privilege of confidentiality.

Reporters got a rare look at the defense's strategy regarding the searches on Monday when Robert Sanger, one of Jackson's attorneys, accidentally sent an e-mail to an attorney for news agencies that contained a motion he planned to file under seal.

The mother's "communications with law enforcement regarding Mr. Miller is a critical issue in the hearings before this court. She met with Mr. Miller and later provided an account of those meetings to the government," Sanger said in the motion. "The prosecution concedes that (she) was expressly informed that Mr. Miller worked for Mr. Geragos."

The motion also included the name of the accuser's mother — which is known to reporters, though prosecutors publicly call her "Jane Doe" — as well as arguments against a prosecution effort to limit her testimony.