Police say that off-duty Sonoma County Sheriff’s Deputy Jeremy Lyle killed his ex-girlfriend and then himself.
Deputy Jeremy Lyle of the Sonoma County sheriff’s office allegedly shot and killed his ex before killing himself during a standoff. The former couple leaves behind three children.
Santa Rosa Police Department Press Release Re: Sonoma County Sheriff’s Deputy Jeremy Lyle Murder/Suicide
SRPD Investigating Murder-Suicide Following Domestic Violence Incident
On Sunday, August 10, 2025, at approximately 7:02 PM, officers with the Santa Rosa Police Department (SRPD) and emergency medical personnel were dispatched to an apartment located in the 4600 block of Quigg Drive. As officers were en route to the apartment, the reporting party advised SRPD Dispatch that the male partner of a woman living in the same complex had gone to her apartment, handed her an infant child, and told her to call 911 because the child’s mother was hurt. The man, identified later as 44-year-old Jeremy Lyle, then left the area in an unknown vehicle and unknown direction. The reporting party remained in her residence with the infant until the police arrived.
The first officers on scene approached the apartment and saw an unresponsive female on a couch in the living room of the apartment. They forced entry into the residence and discovered a deceased female who appeared to have suffered at least one gunshot wound. The officers also located twin toddlers in a back bedroom of the residence. All three children are believed to be those of Lyle and the deceased victim, Mari Bonnici, age 38. None of the children were injured during this incident and are currently being cared for by family members.
As officers were actively searching for Lyle, SRPD Dispatch received information that Lyle was an off-duty Deputy Sheriff employed by the Sonoma County Sheriff’s Office. At approximately 7:32 PM, SRPD Dispatch received information that Lyle’s personal truck was parked in the parking lot of the Sonoma County Coroner’s Office, located at 3336 Chanate Road. Officers immediately responded to the area and blocked both directions of travel on Chanate Road as a precautionary measure for public safety.
Officers saw Lyle standing in the bed of his truck, holding a handgun behind his back. The officers initially at the scene attempted to negotiate Lyle’s peaceful surrender without success. Members of the SRPD SWAT and Hostage Negotiations Team (HNT) responded and assumed the negotiations at approximately 9:00 PM. The negotiations team communicated with Lyle until approximately 2:00 AM, when Lyle died of a single self-inflicted gunshot wound.
Detectives with the SRPD Violent Crimes Team (VCI) and the Sonoma County District Attorney’s Office have been actively investigating this incident throughout the night. Based on their preliminary investigation, they believe Lyle and Bonnici had been in a domestic partnership before their separation. Detectives believe this incident is related to domestic violence. The investigation also determined that both Lyle and Bonnici were employed by the Sonoma County Sheriff’s Office at the time of this incident. Lyle, a Deputy Sheriff, and Bonnici, a Detention Specialist, were both off-duty when this incident occurred. There were no previous reports of domestic violence involving Lyle or Bonnici.
This is an active, ongoing investigation. The motive for this incident is still being investigated. More information may be released as it becomes available.
Anyone experiencing domestic violence in Sonoma County can access compassionate and comprehensive support through the Family Justice Center of Sonoma County and the YWCA Sonoma County. The Family Justice Center, located at 2755 Mendocino Avenue, Suite 100, in Santa Rosa, offers a safe and welcoming environment where survivors can receive legal assistance, counseling, advocacy, and other virtual services. They can also be reached by calling 707-565-8255.
The YWCA Sonoma County provides the region’s only 24/7 domestic violence crisis hotline and operates a safe house shelter, trauma-informed counseling, and support groups for individuals and families. Their office is located at 811 Third Street in Santa Rosa, and their crisis hotline is 707-546-1234.
This is the ninth homicide and third murder-suicide in the City of Santa Rosa in 2025.
Santa Rosa Police Department case number 25-8839. https://alrt.se/u/YGGniLsYERb
Sonoma County Sheriff’s Office Press Release Re: Deputy Jeremy Lyle Murder/Suicide
Santa Rosa Police Investigating Murder-Suicide Involving Sheriff’s Office Personnel
The Sonoma County Sheriff’s Office family is grieving an unimaginable loss. Two members of our department died in a heartbreaking incident on August 10, 2025, when an off-duty deputy fatally shot his former partner, Detention Specialist Mari Bonnici, before taking his own life.
Deputy Jeremy Lyle, who was hired in March 2015 and had been serving as a resident deputy in Timber Cove since October 2019, was involved in a standoff with law enforcement following the shooting. The standoff ended when Deputy Lyle died from a self-inflicted gunshot wound, witnessed by deputies and officers from the Santa Rosa Police Department at the scene.
This tragic event is particularly shocking because it involves a law enforcement officer. We recognize the profound shock and concern that this incident brings to our community. Both the Sheriff’s Office and the community place immense trust in those who are dedicated to serving and protecting. No level of training or experience can fully prepare us for such a tragedy.
We extend our deepest condolences to both families and loved ones. We are grieving alongside them and are working to support our Sheriff’s Office family. We ask for privacy for Mari’s family and members of the Sheriff’s Office as we grieve and navigate this heartbreaking time.
The Santa Rosa Police Department (Case #25-8839) is conducting a criminal investigation into this incident. For media inquiries regarding the homicide investigation, please call SRPD Sgt. Patricia Seffens at (707) 543-3634.
Prepared by: Sergeant Juan Valencia, Public Information Officer
Media Inquiries: (707) 565-3941