Twelve-year-old Rebecca was last seen at a service station in Spokane, Washington on October 21, 1991 with her eleven-year-old friend and elementary school classmate, Iryll "Nicki" N. Wood at the time. Neither girl returned to their homes that evening.
Two hours after the girls' disappearances were reported to the police, Nicki's body was found under a pile of burning pine needles, strangled to death. Her remains were located in the Seven Mile area near Riverside State Park, north of Spokane. There was no evidence of Rebecca's whereabouts at the scene.
Michael W. Tarbert resided in a cabin near the location of Nicki's body in 1991 and he knew her mother. He was an admitted alcoholic and drug addict and had been in trouble with the law several times before.
He said he'd given the girls a ride home from a neighborhood store on the day they were abducted, but he dropped them off safe a block from Nicki's home and had nothing to do with their disappearances. Bloodhounds tracked Michael's scent from his cabin to where Nicki's body was found, and they also smelled the two girls' scents at his cabin.
Authorities discovered he was wanted on unrelated charges; his middle-aged former landlady said he had sexually assaulted her in a secluded area not far from where Nicki's body was later found, and also stolen $400 from her purse.
Michael was arrested the day after the girls' disappearances, but authorities lacked the evidence to file charges against him in their cases. He was convicted of first-degree rape and theft in his landlady's case in 1992 and sentenced to eleven years in prison. He was charged with both of the girls' murders in March of 1996.
The prosecution had a witness who saw Rebecca and Nicki get into Michael's car on the afternoon they were abducted and two prison inmates who stated Michael told them he'd killed the girls while under the influence of drugs.
DNA technology (which wasn't available at the time the girls went missing) later showed that blood found on Michael's pants had probably came from Rebecca.
Michael entered a no contest plea to two counts of first-degree manslaughter in May of 1998, four days before his trial was scheduled to begin. He maintains his innocence and said he only took the plea deal to avoid a possible first-degree murder conviction and life sentence. Michael was sentenced to 20 years in prison for the girls' homicides.
Rebecca's remains have never been located. Her nickname is "Becky" and she has dark blonde hair and brown eyes.