Here's the background on the Darby case. In the text below, "defendant" is Rush.
"At approximately 10:00 p.m. on January 19, 1991, Trudy Darby was working at the K & D convenience store in Macks Creek, Camden County, Missouri. Just prior to closing the store for the evening, Ms. Darby noticed a suspicious looking man standing outside the front of the store. She immediately telephoned her home and spoke to her son, Waylon Darby, whom she asked to come to the store to help her close up. That telephone call ended abruptly.
Before her son arrived to help, Trudy Darby was abducted at gun point by at least three men. Upon arriving at the store and discovering that his mother was gone, Waylon Darby called the Camden County Sheriff's Department. Trooper Jimmy Mays of the Missouri State Highway Patrol arrived at the scene and "processed" the store and surrounding area. Despite extensive search efforts that evening, Trudy Darby was not found.
On January 21, 1991, a concerned citizen heard a report from one of his neighbors that he heard a gunshot near the Little Niangua River on the night of Ms. Darby's abduction. After investigating himself and discovering what appeared to be blood and blond hair on the road near the river, the citizen contacted Deputy Crocker of the Camden County Sheriff's Department, who in turn contacted Trooper Mays, and together the two officers went to the river and investigated.
They discovered the blood, hair and a spent .38 caliber shell casing near the river. The two officers also discovered that the flow of the water in the river created a whirlpool near a bridge, and they believed that anything thrown in the river would have either stayed near the whirlpool or would have not floated very far downstream.
Next, the officers contacted the Missouri Highway Patrol and requested a helicopter search along the river. The helicopter search resulted in locating a nude female body that was about four feet under water and approximately three-quarter's of a mile downstream from where the blood, hair and shell casing were found. The body was identified as Trudy Darby.
The blood and hair found on the road near the river were later determined to match Trudy Darby's blood and hair by the Missouri State Highway Patrol Crime Laboratory.
An autopsy was performed by Dr. Jay Dix on Trudy Darby's body on January 22, 1991. Dr. Dix determined that Trudy Darby's death was caused by two gunshot wounds. The first shot entered the right side of her head creating a gutter wound across her right ear, and the bullet then lodged in her skull after traveling about one inch. The trajectory of the bullet indicated that it came from behind and to the right of the victim. The second shot entered the back of Ms. Darby's head and traveled up through her brain before coming to rest below her scalp.
The investigation into who abducted and murdered Trudy Darby revealed little until the Summer of 1994.
Between 1992 and 1993, Defendant was living with family members near Kansas City, Missouri, and during his stay there he revealed to Elizabeth Corpening that he was involved in the abduction and murder of Trudy Darby. Ms. Corpening was disturbed by this revelation but did not take it too seriously.
Thereafter, in 1993 Defendant revealed to Carl Blakely, a former neighbor of Defendant, that he was involved in the abduction and murder of Trudy Darby. However, this time Defendant's revelation was taken seriously and was reported to Trooper Mays. During the same time period, Gretchen Chastain, a former girlfriend of Defendant, also reported to Trooper Mays that Defendant had revealed to her that he was involved in the abduction and murder of Trudy Darby.
Armed with these reports, Trooper Mays had Defendant arrested. After his arrest, Defendant was interviewed by three officers. One of the officers was a juvenile officer because at the time of the murder, Defendant would have been fifteen years old. At the beginning of the interview, Defendant denied his involvement in this crime. However, later during the interview, Defendant changed his mind and revealed that he was present during the commission of the crimes. Defendant also implicated his brother and one other individual.
It appears that Defendant, together with his brother and at least one other person, arrived at the K & D convenience store on January 19, 1991, with the purpose of robbing and abducting Trudy Darby.
After entering the store and taking money from the cash register, Trudy Darby was dragged out of the store and thrown into the trunk of their automobile. Trudy Darby was then taken to a barn located near the convenience store where she was repeatedly raped and beaten by Defendant and the other persons involved. She was then shot once in the head and placed back into the trunk of their automobile. Defendant and his co-conspirators then drove to the Little Niangua River and opened the trunk and discovered that Trudy Darby was still alive. She was shot in the head again. Her body was then thrown into the river.
During Defendant's incarceration pending trial on this matter, he revealed to at least three inmates that he was involved in the abduction and murder of Trudy Darby. These three inmates each testified against Defendant.
One of the inmates was Edward Thomas, with whom Defendant became acquainted at the Fulton Diagnostic Center. Defendant was under the mistaken belief that Edward Thomas, a "jailhouse lawyer," could help him "beat" the charges pending against him. During the course of several conversations and some thirteen hand-written letters to Edward Thomas, Defendant revealed his involvement in the murder of Trudy Darby.
Thereafter, Edward Thomas turned over all the letters he received from Defendant and revealed the substance of his conversations with Defendant to the Camden County Sheriff's Department. These letters were all introduced into evidence by the prosecution during Defendant's trial.
Defendant did not testify on his own behalf at trial nor did he present any evidence on his behalf. Defendant was convicted by a jury of first degree murder and kidnapping and was sentenced to life in prison without eligibility for parole or probation."