A man who pleaded no contest to murdering his lover’s husband testified Thursday that the woman had no involvement in the killing of the prominent hairdresser at his Woodland Hills home.
Called to the stand by the defense in Monica Sementilli’s murder trial, Robert Baker acknowledged being involved in a relationship with her for “roughly about a year” before the Jan. 23, 2017, stabbing death of her husband, Fabio. He also told jurors that he had killed the 49-year-old victim.
“Did she have anything to do with the planning or the execution of the plan to kill Fabio Sementilli?” one of the woman’s attorneys, Leonard Levine, asked Baker.
“No,” Baker responded.
“You’re sure?” the defense attorney asked.
“I’m positive,” he responded.
Sementilli, now 53, is charged with murder and conspiracy in connection with the stabbing death of her husband in his back yard, shortly before the couple was set to celebrate their 20th wedding anniversary.
The murder charge includes the special circumstances of murder for financial gain and murder while lying in wait.
Baker, described by a prosecutor as carrying on a torrid affair with Monica Sementilli, pleaded no contest in July 2023 to first-degree murder and conspiracy to commit murder and admitted the two special circumstance allegations. Baker, now 62, was sentenced to life in prison without the possibility of parole — the same sentence that she could face if she is convicted as charged.
A third defendant, Christopher Austin, 39, pleaded no contest in January to second-degree murder and testified earlier this month that his longtime friend, Baker, told him that she wanted her husband dead. He acknowledged that he did not personally speak to the woman about the crime.
In his first day on the stand, Baker said, “I murdered him (Fabio Sementilli) because I wanted her.”
“Well, you kind of had her already, but not the way you wanted or what?” the defense attorney asked.
“Absolutely,” Baker responded. “I didn’t have her the way I wanted her … I wanted her to be around me and with me more — like all the time.”
Baker said that he and his lover had talked about whether she was going to leave her husband and that “it didn’t seem like it was really going to happen.”
“I didn’t push it because I didn’t want to run her away,” Baker told the downtown Los Angeles jury hearing the case against Sementilli.
He said he and Sementilli lightly touched on the issue of divorce, but said he could tell that “she wasn’t gonna do that, it wasn’t gonna happen.”
The 62-year-old Army veteran acknowledged that he did time behind bars for lewd and lascivious acts involving a 15-year-old girl, with whom he subsequently “got together” and performed in the “adult entertainment business” and that he later worked as a racketball league director at a Woodland Hills gym, where he met Sementilli.
Baker — who is due back on the stand for more questioning Friday — said he eventually met Fabio Sementilli and the couple’s two daughters. But he said the two kept their affair secret “in every way possible” mainly at her behest.
He said that their meetings were “very sporadic” and that “she called the shots on that based on her schedule.”
One of the woman’s attorneys, Blair Berk, acknowledged in her opening statement that her client had been involved in an extramarital affair, but told jurors that she was not involved in any plot with her lover to kill her husband.
The defense attorney told jurors that Baker decided to take things into his own hands and kill his lover’s husband without any involvement from her after she made it clear that she had no interest in leaving her husband.
Berk said that there was “no financial motive” for Sementilli to want her husband dead, telling jurors that her client “sought comfort” from Baker after her husband’s killing while having “no idea that Robert Baker had done the awful thing that he did.”
Deputy District Attorney Beth Silverman told jurors that Sementilli was the “mastermind” behind her husband’s slaying and was the only one who knew the narrow time frame that he would be alone at the home.
Sementilli sent hundreds of naked photos of herself to Baker during their affair, in which they were “also swinging with other people” while she was simultaneously “living two lives,” according to the deputy district attorney.
After her husband’s killing, Sementilli posed as a “grieving widow” while continuing her torrid affair with Baker, leading her two teenage daughters to text her about why she was out so late at night, Silverman said.
Both of the daughters Sementilli shared with her husband testified during the trial, each telling jurors that they believed that their mother is innocent. They said they had no idea that she was having an extramarital affair until after her June 2017 arrest in connection with the killing, although her older daughter, Gessica, testified that she had found Baker in her mother’s bed one morning.
Sementilli’s older sister, Anna Crescentini, testified Thursday that she considered Sementilli her best friend but knew nothing about the affair before her brother-in-law’s killing, saying that she believes her sister was concealing an affair and her lifestyle but had nothing to do with the murder.
Upon being shown explicit nude photos that Sementilli allegedly sent Baker of herself in the weeks after the killing, the defendant’s sister said she had no idea about it at the time. She acknowledged that she did recognize her sister’s wedding ring.
Jurors also heard a series of courthouse lockup recordings of conversations between Sementilli and Baker, including one in a Van Nuys courthouse lockup shortly after they were taken into custody. Baker can be heard repeatedly expressing his love for Sementilli and telling her that he’s “all in” and that he thinks they should get married.
“Just because we fell in love does not make us criminals,” Sementilli can be heard telling Baker at one point.
Sementilli and Baker have remained behind bars since their arrests in June 2017 and charged with murdering her husband, with a conspiracy charge subsequently being added against them. The two were indicted just over two months later on the same charges, and have remained in county jail.
Austin has also remained behind bars since his arrest.