Probationer charged with murdering woman, trying to kill victim’s mom

Diane Sieker photo

A probationer accused of killing a 58-year-old Anza woman and severely injuring the victim’s mother during an attack at their residence was charged Thursday, March 12, with murder and other offenses.

Karina Sarah Valdivia, 32, was arrested Monday, March 9, following a Riverside County sheriff’s investigation into the slaying of Karen McCoy.

Along with murder, Valdivia is charged with attempted murder and a sentence-enhancing allegation of inflicting great bodily injury on a person over 70 years old.

The defendant is being held in lieu of $1 million bail at the Smith Correctional Facility in Banning and was slated to make her initial court appearance Thursday afternoon at the Southwest Justice Center in Murrieta.

According to Riverside County Sheriff’s Sgt. Rick Espinoza, in the predawn hours Monday, Valdivia allegedly attacked McCoy and her mother,identified by family members as Suzanne Martinez, for unspecified reasons at the victims’ residence in the 60000 block of Coyote Canyon Road, near El Campo Road.

Deputies were called to the residence during the alleged assault and discovered McCoy dead and her mother suffering from life-threatening injuries. The elder woman was taken to a trauma center, where she remains in serious but stable condition, investigators said.

McCoy’s son, Nicholas McCoy, started a GoFundMe campaign to raise money for hospital and funeral expenses. The effort has netted over $6,000. The page can be found at

Espinoza said Valdivia was detained and questioned at the house,culminating in her being booked into jail.

A possible motive for the attack was not disclosed.

According to court records, the defendant has a prior misdemeanor conviction for driving under the influence.