Scheper issued tentative rulings Tuesday, including blocking Gibson from testifying in the trial.
She also blocked jurors from seeing a video defense attorneys for Deputy James Mee wished to show.
The video features Gibson being booked into jail during his DUI arrest, and a TV ad he made three years earlier supporting the L.A. County Sheriff's Dept.
Scheper also ruled that Sheriff Lee Baca should not to testify unless he directed orders against Mee. She said Baca's and Gibson's testimony were not relevant to the trial.
Mee, who is Jewish, claims he suffered religious discrimination by superiors after arresting Gibson in 2006, and that he was ordered to remove the actor-director's anti-Semitic rants from a report.
He claims he was passed over for promotions and suffered other reprisals because of the case and that he was personally offended by Gibson's remarks.
During the July 2006 DUI arrest in Malibu, the actor said, among other things, that Jews were responsible for all the wars in the world. He later issued an apology admitting to making "despicable" remarks and attributed his behavior to alcoholism.
Scheper said she would make final ruling on Feb. 14. Jury selection is expected to begin next week.
The judge said prospective jurors will undoubtedly have heard of Gibson's arrest, but the way Mee has presented his case renders Gibson and Baca's testimony unnecessary.
Gibson's reputation was damaged for years after details of the arrest and his anti-Semitic and sexist rant was leaked.
The actor apologized for his conduct, and his conviction was expunged in 2009 after he completed all the terms of his sentence
Mee remains a deputy, although he no longer patrols for drunken drivers in the coastal community of Malibu where Gibson was arrested.
The Associated Press contributed to this report.