Santa Maria, Calif. ? As the prosecution nears the end of its case against Michael Jackson, jurors face a dilemma: How much should they believe testimony from key witnesses who have admitted past lies?

Prosecutors insist the family of the boy who accused Jackson of molesting him lied only under pressure — first from an abusive father and then from Jackson and his associates.

But defense attorneys, who could begin their case later this week, will urge jurors to discount the family’s testimony altogether because of those previous false statements.

Whether jurors believe the family’s accounts will depend in part on how well the prosecution has corroborated their statements during its eight-week case.

Some of the claims by the boy’s mother — such as her admission that she once feared her family would disappear from Jackson’s Neverland estate in a hot-air balloon — may have sounded outrageous, said Ann Bremner, a trial analyst and former prosecutor.

“Sometimes madness is wisdom. It may sound kind of wackadoodle, but this is his world,” Bremner said. “Everyone knows that Michael Jackson has a separate reality.”

But the mother may have gained credibility on other issues. For example, to support her claim that she feared her family was in danger, prosecutors showed videotapes found in a private investigator’s office to demonstrate that Jackson associates had closely monitored the boy’s family while he, his mother and siblings were allegedly being held captive by Jackson at Neverland.

The mother also said she was “acting” in a February 2003 videotaped interview in which her family praised Jackson. She said every moment was scripted by a Jackson associate.

The woman also admitted lying in a 1999 lawsuit against J.C. Penney when she said her then-husband was an honest person and had never abused her. The family received a $152,000 settlement after alleging they were beaten by security guards at a J.C. Penney store.

Dist. Atty. Tom Sneddon said the woman had lied because she feared her husband would beat her if she told the truth.