Did Monica Sementilli conspire with the man she was having an affair with to murder her husband?

Fabio Sementilli was a superstar in the beauty business. He began cutting hair in Toronto, Canada, and eventually moved to Los Angeles when he was promoted to an executive position at Wella. He settled in a home in Woodland Hills with his wife Monica and their two teenage daughters.

On Jan. 23, 2017, Fabio was in his backyard by the pool when two people broke into the home and stabbed him to death. According to prosecutors, the suspects staged the scene to look like a robbery gone wrong. But when Los Angeles Police Department detectives began investigating the murder, they said they found blood at the scene that didn't belong to Fabio. And they said they also found evidence that his wife was having an affair at the time.

Jan. 23, 2017 | 3:26 p.m.: Monica Sementilli's alibi  

On the day Fabio was killed, prosecutors said a neighbor's security camera captured Monica Sementilli leaving home in her black Ford F-150 pickup truck. She was headed to Target where prosecutors said she was establishing her alibi. Before Monica entered the store, according to prosecutors, there is video where it appears an individual got into Monica's truck. Prosecutors said that person was Robert Baker, a local racquetball coach who Monica had been having an affair with for about a year prior to Fabio's murder. Monica's defense attorneys have disputed the prosecution's interpretation of the video from the parking lot. According to the district attorney, Monica then went alone into the Target store and began shopping.  

Jan. 23, 2017 | 4:18 p.m: Suspects caught on camera

A neighbor's security camera captured two hooded figures jogging near Fabio's house right around the time of the murder. According to prosecutors, the person in the green hoodie was Baker. And prosecutors said that Baker and the unknown co-conspirator entered the Sementilli home and attacked Fabio from behind. They then staged the scene to look like robbery.

Jan. 23, 2017 | 4:32 p.m.: Monica Sementilli pictured at Target the day of her husband's murder 

At 4:32 p.m. on the day of Fabio's murder, Monica Sementilli was seen on surveillance video walking out of the Target store and, according to prosecutors, she was fixated on her phone and likely monitoring her home surveillance cameras remotely. Prosecutors also said that around the time of Fabio's murder, phone records showed that Monica's iPhone was connected to her home's IP address and her phone was consuming a large amount of data consistent with streaming live video.

The prosecution stated in pre-trial motions that Monica was monitoring the comings and goings at her home so that Baker and the unknown accomplice could enter and kill Fabio "without any interruption." But according to Monica's defense team, there is no evidence that can prove what exactly she was watching on her phone at that time. In court documents, the defense raised the possibility that Monica could have been remotely streaming a TV show.   

Jan. 23, 2017 | 4:53 p.m.: The getaway car  

About 35 minutes after the hooded joggers were seen near the Sementilli home, at 4:53 p.m., Fabio's black Porsche was seen on the same neighbor's security camera being driven away. Prosecutors said this was Baker and his unknown co-conspirator leaving the crime scene. According to detectives, the Porsche was discovered two days after the murder parked about five miles away from the Sementilli home. Prosecutors also said Baker's blood was found inside the Porsche.

Jan. 23, 2017 | 4:54 p.m.: A daughter's heartbreaking discovery

Just one minute after the black Porsche is captured, Monica and Fabio's daughter Isabella's vehicle was captured on a security camera as she is returning home. Isabella, who was 16 years old at the time, discovered her father's body and called 911. A few minutes later, Monica arrived back home.      

February – June 2017: The investigation into Fabio Sementilli's murder

As detectives began investigating Fabio's murder, they said they discovered DNA at the crime scene that belonged to Baker. His DNA was in the database because he was a registered sex offender. According to prosecutors, Baker cut his left index finger when he killed Fabio and that's why his blood was at the scene.   

According to the indictment, Investigators also learned that in the year leading up to Fabio's murder, Baker made thousands of calls and texts to Monica.  

In February 2017, an LAPD detective went to visit Monica at her home. Prosecutors said that when the investigator asked Monica about Baker, she told them she wasn't sure of his last name.   

For the next few months, investigators said they surveilled Monica and Baker's secretive romance and said the relationship continued after Fabio's murder. According to the district attorney, the couple took two trips to Las Vegas and a trip to Myrtle Beach together. 

June 14, 2017: Monica Sementilli and her then-boyfriend Robert Baker arrested

LAPD detectives said they came up with a plan to secretly record Monica and Baker while they were together. On June 14, 2017, Monica and Baker were pulled over in her Mustang under the guise of a traffic stop and were told that the car they were driving might have been stolen. According to the prosecution, the officers then handcuffed Monica and Baker and put them in the back seat of a police car, which was wired for sound so that they could be recorded.

The detectives who had been investigating Monica and Baker for months said they were listening to them from a van parked nearby. And that's when investigators said Monica was recorded telling Baker, "Somebody must have talked. Somebody is doing this to us." The couple was then taken to the LAPD Van Nuys Station where they were placed in separate cells and questioned by detectives about the murder of Fabio.  

• Wife of slain hairdresser Fabio Sementilli arrested for murder
  

Later that day, investigators said they told Monica that Baker's blood was found at the crime scene. According to detectives, Monica explained why Baker's blood would be inside her home. She told them that she "cracked" Baker on the finger with a racquet and he bled all over the racquetball court, so she gave him a towel and then brought that bloody towel home with her. 

Aug. 14-18, 2017: The grand jury hearing  

The prosecution presented its case to a grand jury in August 2017. They described Monica's actions on the day her husband was killed in detail and said she was establishing her alibi for the time of the murder.   

The prosecutors also presented evidence that six months before Fabio's murder, Monica communicated with a security camera company to upgrade the system at her home. The upgrade allowed her to remotely access her surveillance cameras from her cellphone. According to the prosecution, Monica forwarded the log in credentials and user manual for her security system to Robert Baker on the same day it was upgraded.   

In the months following Fabio's murder, prosecutors said that while Monica was posting on social media that she was grieving her husband's death, she was also secretly spending time with Baker. Friends of Monica and Baker's testified that they went out on double dates and saw affectionate behavior between the two. At the conclusion of the hearing, Monica and Baker were indicted by the grand jury for murder and conspiracy.  

Aug. 31, 2017: Defendants plead "not guilty" 

On Aug. 31, 2017, both Monica Sementilli and Robert Baker pleaded "not guilty" to the murder of Fabio Sementilli.   

Monica Sementilli's defense presents its case  

On Jan. 3, 2018, Monica's defense team filed a motion to set aside the indictment against her. Among their arguments, they stated that during the grand jury hearing, the prosecution presented evidence of Monica's character that was irrelevant.

The defense said, "the evidence presented against Ms. Sementilli establishes that she was a woman having an affair that she wished to keep secret. Any additional allegation that she wanted to have her husband murdered, or stood to benefit from his murder, or orchestrated his murder with Mr. Baker, was based on pure speculation."   

The defense also stated that the prosecution presented no communication between Baker and Monica that was evidence of an agreement to murder Fabio. The defense also took issue with the surveillance footage in the parking lot that the prosecutors claimed to see Baker getting into Monica's truck. They stated in their motion that "... the video quality is so grainy, and the focal point so distant, so as to be borderline unwatchable," and you cannot see an individual leave Monica's truck.

July 7, 2023: Robert Baker's dramatic plea change  

On July 7, 2023, Baker changed his plea from "not guilty" to "no contest." At his sentencing hearing, the judge explained to him that a "no contest" plea is essentially the same as a "guilty" plea and asked if he understood to which Baker replied, "Yes, sir." Baker was sentenced to life in prison without the possibility of parole. Monica's attorneys had previously attempted to have her case severed from Baker's, which the judge denied. By pleading "no contest," Baker created a significant change in court proceedings going forward. Now, Monica will be tried separately, without Baker, for the murder of her husband, Fabio. 

Feb. 24, 2024: "48 Hours" talks to Robert Baker  

"48 Hours" went to see Robert Baker in jail, and said Monica had nothing to do with the murder of Fabio and she never knew that he was Fabio's killer. Baker also told "48 Hours"  that he's no longer in touch with Monica and he has not decided if he will testify at her trial.  

Monica Sementilli faces trial  

Monica's trial is scheduled to begin on April 2, 2024. Gessica and Isabella, the daughters she shared with Fabio, are standing by their mother. Gessica spoke at Robert Baker's sentencing and said, "we will continue to stand by our mother as we have done for the last six years, and we will fight for her innocence." 

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