Full Notification

For immediate release: November 26, 2025 
By: Community Engagement Liaison Kelsey McCarthy 

Cloverdale Homicide Suspect Dies by Self-Inflicted Gunshot Following Armed Standoff

The Sonoma County Sheriff’s Office and Petaluma Police Department are releasing updated information regarding the homicide investigation that began on November 22, 2025, in Cloverdale and the subsequent armed standoff in Santa Rosa.

Incident Overview – Cloverdale Homicide:
On November 22, 2025, at approximately 4:47 p.m., Sonoma County Sheriff’s deputies responded to a reported shooting in the 300 block of Cloverdale Heights Way in Cloverdale. Deputies and responding officers from the Cloverdale Police Department located an adult female victim suffering from a gunshot wound. Despite immediate life-saving efforts, the victim was pronounced deceased at the scene. Her identity is pending official confirmation and notice to next of kin.

Detectives identified the suspect as 56-year-old Lawrence Cassidy, a resident of Cloverdale. Cassidy fled the area in a white Ford SUV, which was later located on 2nd Street near Matheson Street in Healdsburg. Investigators learned Cassidy was no longer in the area but was possibly at a residence in the 1500 block of Brush Creek Road in Santa Rosa. 

SWAT Deployment and Armed Standoff:
The Sonoma County Sheriff’s Office authored a search warrant and obtained an arrest warrant for Cassidy based on the severity of the crime and information that he was likely armed which prompted the deployment of specialized units. On November 23, 2025, at about 1:26 a.m., the Sonoma County Sheriff’s Office deployed its SWAT Team, Hostage Negotiations Team, and Explosives Ordnance Disposal Unit to the Brush Creek Road property after receiving credible information that Cassidy was present and armed. Two occupants of the main residence were safely evacuated.

Within minutes of arrival, Cassidy, who was in an outbuilding on the property, fired multiple gunshots towards SWAT personnel. During a three-hour standoff, one round is suspected to have struck the armored rescue vehicle. No deputies were injured. Given Cassidy’s actions, SWAT personnel deployed chemical agents to encourage a peaceful surrender, and negotiators made repeated attempts to contact Cassidy, but he did not respond. 

Due to the ongoing threat, the Santa Rosa Police Department issued a shelter-in-place order for the surrounding neighborhood and provided an agency assist by deploying their SWAT team on the perimeter.

At approximately 4:55 a.m., after deploying a drone and a bomb-disposal robot for interior observation, SWAT personnel entered the outbuilding and located Cassidy deceased from a self-inflicted gunshot wound. A semiautomatic handgun was recovered near him.

Independent Critical Incident Review:
Because this incident involved a death during a law enforcement operation, the Sonoma County Sheriff’s Office activated the Sonoma County Critical Incident Protocol. The protocol ensures investigations into significant incidents involving law enforcement are conducted thoroughly, impartially, and free from conflicts of interest.

In accordance with the protocol:

• The Petaluma Police Department is the lead investigating agency in conjunction with the Sonoma County District Attorney’s Office are conducting the independent investigation into the standoff and Cassidy’s death.
• The Marin County Sheriff’s Office Coroner’s Unit is responsible for identification and autopsy results.

The homicide investigation is active and being led by the Sonoma County Sheriff’s Office; the Petaluma Police Department is not involved in that investigation.

The joint response between neighboring agencies reflects a shared commitment to community safety, effective communication, and transparency during critical incidents. 

Additional details may be provided as they become available.

Media inquiries related to the incident, please contact:
PPD Lt. J. Walsh – (707) 776-3743 | [email protected]

Media inquiries related to the personnel at the Sonoma County Sheriff’s Office, please contact:

Sonoma County Sheriff’s Office Public Information Officer at 707-565-3941