CASTRO VALLEY (CBS SF) – A San Leandro woman has pleaded guilty to second-degree murder for the murder of her ex-husband in Castro Valley in unincorporated Alameda County in 1990, prosecutors said.

Cheryl Ann Drace, 61, entered her plea in late April just before her trial was slated to begin in Alameda County Superior Court and will be sentenced by Judge Allan Hymer on July 14, according to prosecutors.

Authorities said Drace and William DeVincenzi, now 53, got married in Reno one day after they fatally stabbed Drace’s ex-husband, 43-year-old Stephen Rudiger, near Chabot Regional Park in Castro Valley on Dec. 27, 1990.

DeVincenzi pleaded guilty to second-degree murder last year and also is scheduled to be sentenced on July 14.

Drace and DeVincenzi are both expected to be sentenced to 15 years to life in state prison.

The case had gone unsolved for more than 20 years but in November 2013 DNA evidence and tips from two informants finally provided enough evidence for authorities to arrest and charge Drace and DeVincenzi.

By that time they had divorced.

When he announced the arrests in 2013, Alameda County sheriff’s

Detective Greg Landeros said Rudiger, who was a foreman at an auto body shop in Oakland, and Drace had a “tumultuous relationship” and had gotten divorced after five years of marriage several months before Rudiger was killed.

However, Rudiger and Drace still lived together while they were in the process of selling their house and there was litigation over the sale, Landeros said.

To complicate matters further, DeVincenzi moved into the house shortly before Rudiger was killed, he said.

Landeros said authorities had always suspected Drace and DeVincenzi but didn’t have enough evidence to arrest and charge them until 2013.

Landeros said Rudiger had three daughters from his first wife, Marie, and has eight grandchildren who he never got to know.

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