How cell phone location sharing helped Los Angeles police solve double homicide, take serial rapist off the street
Cell Phone Tracking Led to the Capture of Los Angeles Serial Rapist in Double Homicide Case
How cell phone location sharing helped – On the evening of November 12, 2021, architect Hilda Marcela Cabrales, 26, and her friend Christy Giles, 24, spent their time in Los Angeles at a Hollywood nightclub before heading to a warehouse party in East Los Angeles. The pair had planned to catch a performance by a DJ they both admired, and their bond was growing stronger, according to Christy’s husband, Jan Cilliers, who was visiting his father in San Francisco during the weekend. Cilliers noted that the two women were becoming “fast friends,” a phrase he used to describe their increasing connection.
A Night That Turned Tragic
By Saturday morning, however, the weekend had taken a dark turn. Cilliers awoke to a troubling realization: his wife’s phone was displaying a location in Los Angeles, far from their San Francisco home. The couple had shared their phone positions regularly, a habit Cilliers explained was rooted in safety. Yet that morning, the shared location was at a place he had never seen before. As hours passed without a response to his texts, his sense of alarm intensified.
It wasn’t until around 5 p.m. that Saturday, November 13, that Cilliers spotted Christy’s phone moving to a hospital approximately three miles away from the mysterious address. The location data revealed that she had been taken there by two masked men in a black Prius with no license plates. According to the men, they had found her unconscious on the street and were acting as “good Samaritans.” Christy was pronounced dead upon arrival, leaving Cilliers in a state of disbelief.
Clues from a Shared Habit
Meanwhile, Hilda’s phone location had also raised concerns. She had a habit of sharing her position with a trusted friend, who served as her emergency contact. That same Saturday, the friend noticed Hilda’s phone pinging at 8641 West Olympic Boulevard—the same address where Cilliers had traced Christy’s movements. This shared habit became a vital piece of the puzzle, leading to a critical insight: both women had been at the same location.
When Hilda’s friend learned of the address, they quickly connected the dots. Hilda had been dropped off at a hospital by two masked men in a black Prius, who claimed to have discovered her passed out on the street. While Hilda survived but was in critical condition, her family faced a heart-wrenching decision two weeks later to remove her from life support. Her sister, Fernanda Cabrales-Arzola, recalled Hilda’s final words: “Thank you for being my sister.” The family opted to donate her organs, and her mother, Dr. Hilda Marcela Arzola-Plascencia, remembered the medical team lining the hallway and “clapping” to honor her daughter’s gift of life.
How the Investigation Unfolded
The LAPD detectives, alerted to the two cases, were able to act swiftly due to the precise location data. Within hours of Hilda’s arrival at the second hospital, detective Jonathan Vander Lee and his partner arrived at 8641 West Olympic Boulevard. The address was soon linked to David Pearce, a suspect in the case. Pearce lived there with a roommate named Brandt Osborn, who was later implicated in the murders.
Pearce and Osborn were arrested in October 2025, months after the incident. The evidence against Pearce included not only the murders of Christy and Hilda but also his history as a serial rapist. During the trial, seven additional women came forward to testify about his crimes. Pearce was ultimately convicted of two counts of felony murder and multiple rape charges. Osborn, however, faced a different fate. The jury could not reach a verdict on his case, resulting in a mistrial.
A Call for Safety in the Digital Age
At a press conference following Pearce’s conviction, Christy’s mother, Dusty Giles, urged the public to take the tragedy as a lesson. “As much as it hurts to lose my baby girl … her sharing her location technology told us where she was,” she said, emphasizing the importance of real-time tracking. The police credited this data as a key factor in identifying Pearce and removing him from the streets.
“You’ll never know when you’re going to not be able to get in touch with somebody,” Dusty Giles added, her voice steady yet filled with emotion. “Please, within your own families, share locations. It could save a life.”
The case highlighted how technology, specifically cell phone location sharing, can bridge gaps in time and space. For Cilliers, the discovery was a sudden, jarring shift. “In less than 24 hours, your world was turned upside down,” Vigliotti asked him during the “48 Hours” investigation. Cilliers responded, “Shattered, yes.” His words underscored the profound impact of the event on his life.
The investigation into the double homicide, titled “Dead Girls Don’t Talk,” was a collaboration between the “48 Hours” team and contributor Jonathan Vigliotti. The program’s encore was available on Paramount+, further amplifying the story’s reach. The case became a symbol of how modern tools can aid in solving crimes, even when the victims are no longer with us.
The Ripple Effect of a Serial Rapist’s Actions
David Pearce’s arrest marked the culmination of a three-year investigation. The trial revealed a pattern of behavior: he had preyed on women, leaving them in dangerous situations. The location data from Christy and Hilda not only tied him to the scene of the crime but also provided a timeline of events that was crucial to the prosecution’s case.
Osborn, who was seen assisting Pearce in transporting the women from their home to the hospitals, was charged with accessory to murder after the fact. His role in the crime, though less direct, was still significant. The trial’s outcome—Pearce’s conviction and Osborn’s mistrial—demonstrated the complexity of linking suspects to multiple crimes, even when evidence is circumstantial.
As the family of Hilda and Christy reflected on their loss, the importance of location sharing became evident. Dusty Giles, speaking at the press conference, emphasized the need for vigilance. “This isn’t just about one family,” she said. “It’s about everyone learning to protect their loved ones through technology.” Her plea resonated with many, as it highlighted a simple yet powerful tool for safety in an increasingly connected world.
The case also sparked broader discussions about the role of digital evidence in criminal investigations. Law enforcement officials noted that without the location data, it might have taken significantly longer to connect the dots. The speed at which the police acted, thanks to the shared information, underscored the value of modern communication methods in solving crimes and bringing perpetrators to justice.
A Legacy of Awareness and Action
For Jan Cilliers, the experience was a mix of fear and determination. “We didn’t know where she was, and we didn’t know what was happening,” he said. The ability to track Christy’s movements in real time provided a lifeline, allowing the police to respond quickly. Hilda’s friend, whose concern was also triggered by the location data, played an equally critical role in ensuring the investigation began without delay.
As the trial concluded, the families of Christy and Hilda found some closure. While the loss of their loved ones was irreplaceable, the justice system had delivered a verdict that sent a clear message. David Pearce, who had been a silent threat for years, was finally held accountable for his actions. The case remains a reminder of the power of technology to turn moments of vulnerability into opportunities for salvation.
The story of Christy and Hilda, as told in “Dead Girls Don’t Talk,” serves as a testament to the importance of staying connected in an unpredictable world. Their lives, though cut short, left a lasting impact, urging others to adopt the same precautions. As Dusty Giles said, “You never know when you’ll need that information to save someone’s life.” The legacy of their tragedy continues to inspire vigilance and innovation in the fight against crime.