Mel Gibson can testify about what he learned from one of Harvey Weinstein’s accusers, a US judge ruled in the rape and sexual assault trial of the former movie mogul.

The 66-year-old actor and director was one of many witnesses, and by far the best known, whose identities were revealed in Los Angeles Superior Court.

Judge Lisa B. Lench ruled on Friday that Gibson could testify in support of his masseuse and friend, who will be known as Jane Doe #3 at the trial.

Weinstein is accused of committing sexual battery by restraint against the woman, one of 11 rape and sexual assault counts in the trial against the 70-year-old.

Prosecutors said that after getting a massage from Jane Doe #3 at a California hotel in Beverly Hills in May of 2010, a naked Weinstein followed her into the bathroom and masturbated.

Weinstein has pleaded not guilty, and denied any non-consensual sexual activity.

Judge rules for prosecution

Weinstein’s attorneys argued against allowing Gibson to testify, saying what he learned from the woman while getting a massage from her does not constitute a “fresh complaint” by the woman under the law by which Gibson would take the stand.

A “fresh complaint” under California law allows the introduction of evidence of sexual assault or another crime if the victim reported it to someone else voluntarily and relatively promptly after it happened.

Prosecutors said when Gibson brought up Weinstein’s name by chance, the woman had a traumatic response and Gibson understood from her that she had been sexually assaulted.

Gibson did not remember the timing of the exchange, but the prosecution will use another witness, Allison Weiner, who remembered speaking to both Gibson and the woman in 2015.

Judge Lench said Gibson’s testimony would depend on how the accuser described the exchange with him when she takes the stand, and she may choose to rule against it at that time.

Weinstein attorney Mark Werksman then argued if Gibson did take the stand, the defence should be allowed to cross-examine him about widely publicised anti-semitic remarks Gibson made during an arrest in 2006, and about racist statements to a girlfriend that were recorded and publicised in 2010.

Courtroom confrontation

Judge Lench said a wider discussion of Gibson’s racism was not relevant to the trial, but she would allow questioning of whether he had a personal bias and animus toward Weinstein.

Gibson’s testimony raises the prospect of two of Hollywood’s once most powerful men, who have undergone public downfalls, facing each other in court.

An email seeking comment from a representative for Gibson was not immediately returned.

Weinstein is serving a 23-year sentence for a 2020 conviction for rape and sexual assault in New York. The state’s highest court has agreed to hear his appeal in that case.

He was subsequently brought to Los Angeles for a trial that began Monday, five years after women’s stories about him gave massive momentum to the #MeToo movement

-AAP