On February 15, 2021, Sheriff's deputies responded to a residence in the 15700 block of Lyons Valley Road in Jamul for a shooting. The victim, sixty-two-year-old Bruce Carl Mueller, was transported to a local area hospital for treatment. The suspect, sixty-four-year-old Guillermo Vallin Morales, was armed with a handgun and refused to exit the residence. Several hours later, Morales was located deceased inside the residence.  

On February 17, 2021, the Medical Examiner's Office conducted an autopsy on Morales. The cause of his death was a penetrating gunshot wound to the head and the manner of death was suicide. His family has been notified of his death. Morales is a resident of Jamul.

Mueller was treated and was eventually released from the hospital. The Rancho San Diego Station Detective Unit continued to investigate. Detectives determined Mueller had told Morales to move out of the Lyons Valley Road residence. An argument ensued and Morales shot Mueller.  

On May 7, 2021, Mueller checked himself back into a local hospital. Unfortunately, Mueller's health declined. He was pronounced deceased at the hospital. 

On May 14, 2021, the Medical Examiner's Office conducted an autopsy on Mueller. His family was notified of his death. The preliminary cause of death was complications from a penetrating gunshot wound to the torso and the manner of death was homicide. Mueller is a resident of the city of San Diego.

Despite the case being solved, the Sheriff's Homicide Unit has assumed responsibility of the investigation due to procedural reasons.

Information from prior release:

On February 15th at 11:55 AM, Rancho San Diego Sheriff's Deputies responded to a call of an adult male who had just been shot at a residence in the 15700 block of Lyons Valley Rd. in the unincorporated area of Jamul.

Deputies arrived at the scene and located the victim outside of the residence.  Deputies safely evacuated the victim from the property and transferred him to nearby paramedics who then transported the victim to the hospital where he underwent surgery for a gunshot wound.  Deputies surrounded the residence, believing the shooting suspect, a 64-year-old male, was still located inside and armed with a gun.  Deputies made multiple loudspeaker announcements advising the suspect to exit the residence and surrender to deputies, which he refused to do.

Based on the suspect's unwillingness to cooperate with patrol deputies and the belief that he was still armed with a gun that he had already used to shoot the victim, the Sheriff's Crisis Negotiations Team (CNT) and Special Enforcement Detail (SED) were requested to respond to the scene in an attempt to safely resolve the incident.  Once on scene, the Crisis Negotiations Team made contact with the suspect via telephone and spoke with him for several hours in an attempt to get him to peacefully surrender.

After several hours of refusing to cooperate with the Crisis Negotiations Team and exit the residence, the Special Enforcement Detail used chemical agents in an attempt to safely force the armed suspect to surrender and exit the residence.  The suspect still refused to exit the residence after the deployment of chemical agents and was later located deceased in the attic of the residence at approximately 04:27 AM on February 16th.  It appeared the armed suspect had suffered a self-inflicted gunshot wound.

The victim in this case is in stable condition at the hospital and his injuries do not appear to be life-threatening.  The follow-up investigation in this case is being handled by the Rancho San Diego Station Detective Unit.

Prepared by:  Thomas Seiver, Lieutenant

Sheriff's Homicide Unit   (858) 285- 6330