Man sentenced 7-years to life for 1972 murder

A man who fatally beat a Coachella Valley woman during a robbery — a crime that went unsolved for four decades — was sentenced Friday to seven years to life in prison.

Michael Jerome Hayes, 66, was convicted last month of first-degree murder for the 1972 slaying of 23-year-old Mary Elaine Costa.

Riverside County Superior Court Judge Charles Koosed was mandated to impose the sentence required under the California penal code at the time of the crime. The murder statute has since been amended, mandating a 25-year-to-life sentence.

Hayes was also given credit for time served, totaling 859 days in county jail. The defendant will be eligible for parole in January 2020.

The nine-woman, three-man jury that found Hayes guilty on May 7 was the second panel to weigh his fate. A jury in February deadlocked 9-3 in favor of conviction, culminating in the retrial.

Hayes’ first wife, Diana Clark, was the prosecution’s key witness and testified that the defendant took her to see Costa’s remains. Clark recalled Hayes pulling her out of bed on a late February night, when she was five months pregnant, and driving her away from the Indio mobile home park where they lived and heading out into the desert, eventually stopping on an unpaved road where no lights were in sight. Laying less than 20 feet from the roadway, Clark testified, was a woman’s body, clad in a “multi-colored dress” and face-down in the dirt.

Clark recalled seeing a blood-stained rock laying nearby. She said she demanded to know what had happened, and Hayes told her that he had killed the young woman for money.

“I said, `What do you mean you killed her for money?’ And he said, `Yeah, and I only got $7,”’ Clark testified.

The witness said Hayes admitted beating Costa over the head because she fought him when he attempted to take her purse.

The defendant told his then-wife that he’d met Costa on a Palm Springs street after leaving his bartender job at the Biltmore Hotel. He knew the victim was a hooker, so he picked her up under the guise of wanting to go somewhere secluded for sex, Clark said.

She described Hayes as physically and emotionally abusive throughout their cohabitation in Riverside County.

“One of his favorite sayings was, `Just remember what happened to the woman in the desert,”’ Clark testified.

Costa’s body was found several weeks after the deadly assault when a real estate investor scouting development opportunities in the area of Avenue 20 and Cottonwood Road in Desert Hot Springs stumbled upon the badly decomposed remains, according to Deputy District Attorney Chris Cook. He said with few leads for investigators to follow, the case quickly went cold.

In December 1976, Clark decided to contact sheriff’s investigators about what she knew, feeling less threatened after Hayes moved to Florida. The case was re-opened, but the investigation concluded within a few months, after apparent difficulties gathering enough evidence to justify filing charges.

The sheriff’s cold case squad renewed the investigation in 2011, culminating in the filing of a criminal complaint.

An Indio judge tossed the case in 2012, saying the four-decade delay undermined the defendant’s right to a fair trial. However, prosecutors prevailed in having the charges reinstated after arguing before a state appeals court.

The defense maintained that Hayes never knew Costa and that Clark — as well as two other ex-wives who testified against him — lacked credibility.