A 73-year-old Hemet man is suspected of poisoning his ailing wife with antifreeze last year, police said.
Sidney Allen Davis was booked Thursday on suspicion of murder, elder abuse and domestic battery.
Shirley Davis, 81, who had Alzheimer's disease, died March 29.
Sidney Davis waited 12 hours before calling police to report that his wife of 37 years was unconscious, Hemet Police Cpl. Mark Richards said. She was taken to Hemet Valley Medical Center, where she died a short time later.
Police began their investigation several weeks after her death when neighbors told them they had heard Sidney Davis implying that his wife had accidentally ingested antifreeze, Richards said.
A short time later, the autopsy confirmed the cause of death and the coroner ruled it suspicious, Richards said.
Davis insisted that his wife accidentally drank antifreeze, but police said his statements were inconsistent.
Authorities have ruled out a financial motive, but suspect Davis grew tired of caring for his sick wife.
"She depended on him," Richards said.
"I think she just became so burdensome that he just didn't want her anymore."
The couple had no children. Davis is being held without bail.