A key prosecution witness in the trial of a woman accused of masterminding her husband’s murder testified Tuesday that a longtime friend told him that she wanted her husband dead, but acknowledged that he did not personally speak to the prominent hairdresser’s wife about the crime.
Christopher Austin — who pleaded no contest in January to second-degree murder for his involvement in the Jan. 23, 2017, killing of Fabio Sementilli — told the downtown Los Angeles jury hearing the case against Monica Sementilli that he told an undercover jailhouse operative shortly after his arrest last October that his friend, Robert Baker, and “the woman he was messing with” were “involved” in the crime.
“The woman he was messing with — do you see her in court?” Deputy District Attorney Heather Steggell asked Austin, who then identified Sementilli sitting across the downtown Los Angeles courtroom.
Monica Sementilli, now 53, is charged with murder and conspiracy in connection with the stabbing death of her 49-year-old 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.
Austin testified that he told the jailhouse operative that “she was supposed to get a lot of money if we did it,” saying that the man he considered “family” told him that she was “loaded” and “wants him gone.” He said he mentioned insurance money because Baker had told him about it.
Austin, who was working as a parole and probation officer dealing with at-risk youths in Oregon at the time of his arrest, said Baker paid for his airline flight to Los Angeles and drove him the same night to a shopping center after getting a text message that Monica Sementilli was going to send her husband out that night.
Austin told jurors that he couldn’t go forward with the attack, but said the two men went the next day to the Sementilli family home to commit the killing after Baker received a text message.
“He said she’s going to the store. We have a small window,” said Austin, who told jurors that he learned then that the victim had a “kid” who might come back to the house.
The prosecution witness testified that Baker put him in the trunk of the rented Nissan and drove to an area where Baker gave him a knife and asked, “Are you with me?”
“Like a dummy, I said, `Yeah’ and followed him,” he said, noting that the two men ran up the hill to the victim’s home.
“He said the front door should be open, meaning unlocked. He told me, he said, `She’s gonna leave the door open,” Austin told jurors.
“… Did he tell you who she was?” the prosecutor asked.
“The defendant,” Austin responded, saying that the door was “indeed unlocked.”
He said Baker told him that the victim should be on the back patio and that the victim didn’t see him until Baker got close to him and tried to yell then.
“Baker covered his mouth and started stabbing him,” he said. “I covered his eyes and stabbed him once.”
He said he got into the passenger side of the victim’s Porsche at Baker’s request and saw Baker — whom he said had told him that it had to “look like a robbery” — returning with a pillowcase before the two men left in the vehicle. Austin said Baker eventually handed him items to throw out the car window and ordered him out of the Porsche before meeting up again with him on a main street.
Austin testified that Baker dumped the clothing they had both been wearing in a trash bin and that he decided to return to Washington state a day early “because I couldn’t be there.” He said Baker stuck a roll of gold coins in his pocket that his friend said was valued at around $10,000 — an item that he said Baker told him had come from the victim’s safe.
“I told him, `I can’t believe you had me do that,” he told jurors.
He said that Baker responded, “It’s done. You’re still a good person,” and that Baker “couldn’t convince me that I was.”
Austin said he subsequently used a “burner” phone to communicate with Baker and began using an app to communicate with encrypted messages.
“He just said, `Don’t say anything … You’re going to be fine.’ I wasn’t O.K.,” Austin testified.
He said he heard once from Baker after he and Sementilli were arrested in 2017, telling jurors that his longtime friend told him not to say anything and not to mention “her” if anybody asked what happened.
He said Baker told him, “If anybody asks you, tell them I did it.”
Under cross-examination by defense attorney Leonard Levine, the prosecution witness acknowledged that he didn’t have any conversations himself with Sementilli about her husband’s killing and didn’t see any text messages from her to Baker.
He admitted that he was “a part” of the killing.
When asked why he didn’t say no to Baker about being involved in the crime, he said, “He was like family and he said that his girlfriend didn’t want him (the victim) around any more.”
He said he had only met Monica Sementilli at a gym and then returned with her and Baker to her home, where he was eventually left alone while the two retreated to a bedroom. He said Baker subsequently told him to remember the layout.
The prosecution witness testified that he didn’t give his full account to the jailhouse operative or Los Angeles police detectives when he initially spoke with them because he didn’t have an attorney with him at the time, and said he has “felt bad” ever since the killing.
“Did you know you were coming down to kill him?” Sementilli’s attorney asked.
He acknowledged that he was, but said he was “hoping it wasn’t going to happen.”
Austin is due back on the stand Wednesday for more questioning.
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.”
Jurors have heard from one of the couple’s daughters, Gessica, who testified she wasn’t aware that her mother and Baker had been engaged in an affair until their arrests by Los Angeles police in June 2017. She told jurors that she and members of her father’s family have stopped speaking to each other after “lots of fights and arguments” since the arrests, noting that she told one of her aunts that she believed her mother is innocent.
The jury also heard a lengthy audio recording of Monica Sementilli and Baker 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.