SAN DIEGO (CNS) - A Chula Vista man pleaded guilty Monday to three murders, including his wife and mother-in-law in a staged car wreck, and was immediately sentenced to six consecutive life terms in prison with no chance for parole.

Michael Eugene Richardson, 60, answered "guilty, your honor" as Superior Court Judge Joan Weber asked him how he wanted to plead to the June 2010 murders of his 39-year-old wife, Thao, and his 72-year-old mother-in-law, Phan Lai.

Richardson, the former owner of a mechanic shop in Poway, also pleaded guilty to first-degree murder in the 1992 death of 38-year-old Jovita Collazo of National City, whose body has never been found.

The defendant, who had faced the death penalty, also admitted a special circumstance allegation of multiple murders. Richardson, who had a 1976 conviction for robbery in North Carolina, had his three life terms doubled under California's "three strikes" law.

Michael Collazo said he has waited 21 years, three months and two weeks for Richardson to admit that he killed Collazo's estranged wife.

"I always knew what you did," he told the defendant in court. "You knew that I knew what you had done."

Jovita Collazo's daughter, Michelle Gutierrez, was 12 when her mother disappeared on April 30, 1992. Gutierrez testified at a preliminary hearing last year that Richardson had molested her for three years.

Outside court Monday, Gutierrez said she has forgiven the defendant but was happy to hear him admit what he did.

"I was in shock," she said.

In the murders of Thao Richardson and her mother, investigators determined that the June 29, 2010, accident scene down an embankment off state Route 67 north of Lakeside was staged.

Autopsies show that Phan Lai's throat was cut and her daughter was likely suffocated.

At the time, Richardson had been charged with sexually assaulting a 17-year-old niece in the Chula Vista home he shared with his wife and mother-in-law.