One of the daughters of a woman on trial in a murder case testified Friday that she had no idea that her mother was having an affair until her arrest in 2017 in connection with the killing of her husband — a prominent hairdresser — at the family’s Woodland Hills home.
Gessica Sementilli, now 26, told the downtown Los Angeles jury hearing the case against her mother, Monica Sementilli, that she found Robert Louis Baker in her mother’s bed once in 2016, and said she called her mother, who explained that he had decided to sleep it off at the home after he had too much to drink at a party.
Her mother explained that one of her female friends had also spent the night at the home, the young woman testified.
“I had no reason to believe otherwise so I believed her,” she said, noting that she thought her father was traveling or working at the time.
Monica Sementilli, now 53, is charged with murder and conspiracy in connection with the stabbing death of her 49-year-old husband, Fabio Sementilli, in his back yard on Jan. 23, 2017, 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, now 62, pleaded no contest in July 2023 to first-degree murder and conspiracy to commit murder and admitted the two special circumstance allegations. He was sentenced to life in prison without the possibility of parole — the same sentence that Sementilli could face if she is convicted as charged..
A third defendant, Christopher Austin, who was arrested late last year following a lengthy investigation by Los Angeles police, pleaded guilty Jan. 17 to second-degree murder. The now 39-year-old man agreed to testify truthfully in exchange for a 16-year-to-life state prison term.
“Tough topic, but up until your mom’s arrest, did you ever know that she was having an affair with Robert Baker?” Deputy District Attorney Heather Steggell asked the couple’s oldest daughter, who was 18 when her father was killed.
“No, not until her arrest,” Gessica Sementilli responded of her mother being taken into custody in June 2017.
She said that she was informed by a firefighter that “your dad’s dead” when she returned home the day of her father’s killing, and that she was told not to look outside. She said she went into the house and found her mother “inconsolable, screaming, crying” and her own younger sister — who had discovered their father’s bloody body — “not speaking.”
The young woman said her mother was “just sad and carrying his sweater around crying” in the days after, but acknowledged that her mother was subsequently often away from home in what the witness said she believed was her mother’s way of coping with her grief.
Gessica Sementilli testified that she had believed her parents were “the epitome of what a loving marriage was and what I strive to look for in a partner,”: while acknowledging that she eventually learned the marriage was not perfect on her mother’s side. She is expected to continue her testimony next week.
Jurors are also expected to hear from Austin before the prosecution wraps up its portion of the case.
In the trial’s opening statements in January, Deputy District Attorney Beth Silverman told jurors that Monica 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.
Monica 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.
One of Monica Sementilli’s attorneys, Blair Berk, acknowledged 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 said in her opening statement that Baker decided to take things into his own hands and kill Monica Sementilli’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 Monica 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.”
Sementilli and Baker have remained behind bars since being arrested by Los Angeles police 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 been behind bars since his arrest last fall.