Police found the bodies of Tracie Wallace and her boyfriend Ronald Williamson in Williamson’s home in Plano, near Dallas, on 1 November 1989. Both had been shot. Charles Hood, who had been living in the house, was arrested in Indiana in Ronald Williamson's car. He was brought to trial in Collin County in Texas, and after the jury convicted him on 29 August 1990, the trial moved into a sentencing stage, at which the prosecution presented its arguments for execution and the defence presented mitigating evidence. As the US Supreme Court reiterated in a Texas case in 2007, "we have long recognized that a sentencing jury must be able to give a reasoned moral response to a defendant’s mitigating evidence – particularly that evidence which tends to diminish his culpability – when deciding whether to sentence him to death." (Brewer v. Quarterman).

Hood's jury heard evidence of his mental impairments and other information about his background. In a near-fatal accident at the age of three, Charles Hood had been run over by a truck and was hospitalized for five months. He was left with permanent physical injuries, and his parents noted behavioural changes too. As a child, he developed a fear of school that was diagnosed as a phobia of being inside buildings. The jury heard evidence that his parents administered "whippings" during his adolescence, sometimes in an attempt to get him to go to school. Hood had learning disabilities, and required special education classes at school. He dropped out of school after failing seventh grade (age 12-13 level), and he later failed the US Army entrance examination three times. At the age of 18, his reading and maths skills were assessed at falling below the sixth grade level (age 11-12), and his language and writing skills put at the level of an eight- or nine-year-old. At the age of 19, Hood was described in an Indiana Department of Corrections report as acting "like a little kid who has been maintained in a fosted [sic] dependency situation," and was "somewhat neurotic," phobic, "very immature emotionally," and "highly dependent." The jury also heard evidence that a psychiatrist had concluded that Charles Hood had significant brain impairment, causing learning disabilities, impaired judgment and poor impulse control. He had diagnosed Hood with "neurophysiological brain dysfunction with probable left temporal cortical and deep temporal limbic brain dysfunction."

After hearing the sentencing phase evidence, the jurors were required to answer two questions ("special issues"), on deliberateness and dangerousness; firstly whether the defendant had acted deliberately and with the reasonable expectation that the death of the victims would result, and secondly whether there was "a probability that the defendant would commit criminal acts of violence that would constitute a continuing threat to society." Affirmative answers to these questions would automatically result in a death sentence.