Andrew Lyons was convicted of two counts of murder and sentenced to death on each count for the killing of his estranged girlfriend, Bridgette Harris, and her mother, Evelyn Sparks. In 2007, as required by Ring v. Arizona,  536 U.S. 584 (2002), the Missouri Supreme Court set aside the death sentence for one of the murders (Evelyn Sparks) because the jury failed to set out findings necessary to impose the death penalty. Regarding the second death sentence (Bridgette Harris), Lyons filed a petition in mandamus, claiming to be mentally retarded and therefore ineligible to be executed. 

Atkins: The Missouri Supreme Court appointed a master who determined Lyons met the statutory definition of “mental retardation,” and the Court found this determination to be supported by substantial evidence. The master heard evidence of four IQ tests, ranging from 61 to 84, and was persuaded by Lyons’ expert who “reconciled the variance” and concluded that Lyons’ IQ fell between 61 and 70. In evaluating evidence of Lyons’ adaptive functioning, the master found deficits in two adaptive behaviors—communications and functional academics. With respect to communication, the master heard evidence of Lyons’ difficulties communicating with his attorneys and experts as well as testimony from family members that Lyons was a loner, withdrawn, unwilling to engage in conversations, and nauseated by having to get ready for school. Regarding functional academics, the limited school records available showed failing or incomplete grades and that Lyons had been in the 10th Grade for three years; his Iowa Basic Skills Test placed him in the bottom 2 percent. The master also determined that these conditions manifested and were documented before the age of 18, and the Missouri Supreme Court deferred to the master’s reasonable inferences from the record. 303 S.W.3d at 526-27.

The Missouri Supreme Court issued a permanent writ of mandamus to prohibit Lyon’s execution and resentenced Lyons to life without parole.