Monica Sementilli is serving a life sentence without the possibility of parole after being convicted of plotting the murder of her husband, celebrity hairstylist Fabio Sementilli, with her longtime lover.
In April 2025, a jury found Monica Sementilli guilty of first-degree murder with special circumstances, concluding that she directed her boyfriend, Robert Baker, to carry out the killing for financial gain and to eliminate the need for a divorce.
Fabio Sementilli was found stabbed to death in January 2017 at the couple’s home in Woodland Hills, California. Prosecutors described the crime as calculated and motivated by greed, betrayal, and an extramarital affair.
Who Was Monica Sementilli?
Monica Sementilli is a former makeup artist and hair model who met Fabio Sementilli in Toronto during the 1990s. At the time, both were living in Canada. Although initially reluctant to leave her extended Italian family, Monica eventually moved to Los Angeles so Fabio could advance his career.
The couple raised two daughters together and also shared responsibility for Fabio’s son from a previous relationship. To friends and colleagues, the marriage appeared stable and affluent.
Fabio Sementilli became a prominent figure in the professional hair industry, working extensively on film productions and serving in an executive education role for an international haircare company. He was well known among peers and clients for his charisma and generosity, and investigators later noted that he had no known enemies.
Who Was Robert Baker?
Robert Baker was a racquetball instructor who met Monica Sementilli at a fitness club in Los Angeles, where he coached her. Witnesses later described him as confident, physically imposing, and dominant in personality.
By 2016, Monica and Baker were engaged in a secret affair. Evidence presented at trial showed that Monica was aware of Baker’s involvement in adult entertainment and his criminal history, which included a prior conviction for a sexual offense involving a minor.
Despite his background, prosecutors said Monica became emotionally dependent on Baker and began planning a future with him that excluded her husband.
The Murder of Fabio Sementilli
On the evening of January 23, 2017, Baker and an accomplice, Christopher Austin, entered the Sementilli property and attacked Fabio in the backyard. Fabio was stabbed multiple times and died at the scene.
The assailants then entered the home, staged the scene to resemble a burglary, and fled in Fabio’s Porsche. The vehicle was later abandoned several miles away.
Fabio’s teenage daughter discovered his body when she returned home, a detail prosecutors described as one of the most devastating consequences of the crime.
Initially, investigators considered whether the killing was connected to a series of residential burglaries occurring in the area. However, several inconsistencies quickly raised suspicion.
How the Plot Unraveled
Detectives noted that valuable items, including a luxury watch worn by Fabio, were left behind, undermining the burglary theory. Additionally, the perpetrators removed a digital video recorder that stored the home’s security footage — a device that was not easily visible or accessible.
Soon after the murder, Monica began repeatedly contacting law enforcement and insurance representatives about collecting more than $1.6 million from Fabio’s life insurance policy. Investigators found her urgency unusual.
Witnesses also noticed Monica openly spending time with Baker shortly after the killing. Baker was observed with a bandaged hand, which later became significant.
Forensic analysis revealed Baker’s blood inside Fabio’s stolen vehicle. Investigators were able to match the DNA to records from Baker’s earlier criminal conviction.
Authorities then uncovered extensive digital communications between Monica and Baker. These included explicit messages exchanged before and after the killing, as well as instructions sent by Monica explaining how to locate and remove the home’s surveillance equipment.
Police placed tracking devices on both suspects’ vehicles and monitored them for months, documenting their continued relationship. The surveillance ultimately led to their arrest in June 2017.
Charges and Trial Testimony
Monica Sementilli was charged with murder with special circumstances, including financial gain and lying in wait. She pleaded not guilty.
Robert Baker was charged with first-degree murder and later accepted a plea agreement, receiving life in prison without parole. Christopher Austin pleaded guilty to second-degree murder and received a sentence of 15 years to life.
At trial, Baker claimed Monica had no knowledge of the plan, testifying that he acted alone out of obsession. Austin contradicted that account, stating that Baker followed Monica’s instructions step by step, relayed through text messages.
Prosecutors presented a timeline showing that critical actions during the murder aligned closely with communications from Monica.
The jury ultimately rejected the defense’s argument that Monica’s secrecy was solely to conceal an affair.
Verdict and Sentencing
In April 2025, the jury found Monica Sementilli guilty on all counts. She reportedly broke down in court when the verdict was read.
During sentencing in June 2025, the judge imposed life imprisonment without the possibility of parole. Family members of Fabio described the profound betrayal they felt, emphasizing that Monica had been embraced as part of their family for decades.
Where Monica Sementilli Is Now
Monica Sementilli is currently incarcerated at the Central California Women’s Facility in Chowchilla. She has continued to maintain her innocence through her legal counsel and is expected to pursue an appeal.
No further court dates have been announced.