Defense attorneys for Travis Bredhold, a Kentucky defendant facing the death penalty for a murder committed when he was 18 years old, are asking a judge to extend the death-penalty exemption for juvenile offenders to those younger than age 21. In 2005, the U.S. Supreme Court (pictured) ruled in Roper v. Simmons that the death penalty was unconstitutionally cruel and unusual punishment when applied to offenders who were under age 18 at the time of the crime. The Court held at that time that a national consensus had evolved against such executions and that the death penalty was a disproportionate punishment for juvenile offenders. In reaching that determination, the Court said that neither retribution nor deterrence provided adequate justification for imposing the death penalty. Justice Kennedy wrote for the majority, "Retribution is not proportional if the law’s most severe penalty is imposed on one whose culpability or blameworthiness is diminished, to a substantial degree, by reason of youth and immaturity." Joanne Lynch, an attorney for Bredhold, told Fayette Circuit Judge Ernesto Scorsone that research indicates that brain maturation continues beyond the age of 18, and the juvenile exemption should be extended, "because people under the age of 21 are almost completely like people under the age of 18. You really don’t mature until you are in your mid-20s." According to Temple University psychology professor Laurence Steinberg, a process called myelination continues into a person's twenties, affecting their ability to plan ahead, analyze risks and rewards, and make complex decisions. In a 2014 paper, Hollis Whitson cited both neurological evidence of the immaturity of late-adolescent brains, as well as examples of how the law differentiates people under 21, including liquor laws, inheritance laws, and eligibility for commerical drivers' licenses. She also found that death sentences for those aged 18-20 were disproportionately applied to racial minorities. From 2000 through 2015, 142 prisoners were executed in the United States for offenses committed before age 21: 87 (61.3%) were black or Latino.