Santa Maria, Calif. ? In a major setback for Michael Jackson, a judge ruled Monday that the jury can hear allegations that the pop star molested or had designs on five other boys, including actor Macaulay Culkin and two youngsters who reached multimillion-dollar settlements with the singer.

Dist. Atty. Tom Sneddon said Jackson’s inappropriate activities with these boys included kissing, hugging and inserting his hands into their pants. He also said there was a pattern of “grooming,” or preparing the boys for molestation, but did not elaborate.

Jackson, 46, is on trial on charges he molested one boy — then 13 — at his Neverland ranch in 2003. In most criminal cases, evidence of past behavior is not admissible against a defendant. However, the California Legislature changed that in 1995, specifically in cases of child molestation and domestic violence.

Sneddon said the testimony about the five cases would show that Jackson has a consistent pattern of abuse.

The incidents allegedly occurred 12 to 15 years ago, and the prosecutor acknowledged that only one of the five boys has agreed to testify at Jackson’s trial. Some of the other testimony would come from the mothers of the two boys who won settlements.

Defense attorney Thomas Mesereau Jr. asked Judge Rodney Melville to exclude the allegations, saying they were based on third parties, many of whom were after Jackson’s money. The reference was to former Jackson employees who sued the singer in the past and lost, and were then ordered to pay the singer $1 million in damages.

And Mesereau said Culkin, a frequent visitor to Jackson’s Neverland Ranch, “has repeatedly said he was never molested.”

Culkin’s publicist, Michelle Bega, said Monday that the “Home Alone” star “is presently not involved with the proceedings, and we do not expect that to change.”

After the judge’s ruling, comedian George Lopez took the stand and told about helping Jackson’s current accuser as the boy battled cancer. Lopez said he came to believe the boy’s father was more interested in money than helping his son. He testified the father accused the comedian of stealing $300 from the boy’s wallet.

Lopez said that he finally cut off the family because of the father’s frequent and aggressive requests for help.

When the father asked what he was supposed to tell his son, Lopez testified that he responded: “Tell him his father’s an extortionist.”

The defense contends Lopez, star of the ABC sitcom “George Lopez,” is among celebrities who were targeted by the accuser’s family in schemes to make money.

Sneddon said one boy from the five earlier cases would come forward and his mother also would testify. That case involved a boy who was allegedly involved in a 1990 incident and received a $2.4 million settlement from Jackson in 1994.

The district attorney also promised testimony from the mother of a boy who reached a multimillion-dollar settlement with Jackson in 1993.

It was unclear exactly what Jackson was accused of doing with each of the five boys, though the 1993 accuser claimed he was repeatedly molested, and Sneddon said the boy in the 1990 case was touched twice over his clothes and once under his clothes.

The judge excluded two other boys named by the prosecution but did not say why.