[2] In an 8–1 opinion written by Chief Justice William Rehnquist, the United States Supreme Court denied Cone's petition for a writ of habeas corpus.

[4] Justice John Paul Stevens wrote a dissenting opinion in which he argued that Cone was denied effective assistance of counsel because his attorney failed to "subject the prosecution's case to meaningful adversarial testing.

[9] In 1982, Gary Cone was convicted and sentenced to death for a crime spree that included the robbery of a jewelry store, a police pursuit, and the murder of an elderly couple.

[11] According to one expert, Cone's long-term drug abuse caused hallucinations and paranoia that "affected respondent's mental capacity and ability to obey the law.

[15] Cone later filed a petition for postconviction relief, in which he argued that his attorney provided ineffective assistance of counsel by waiving his closing argument and by failing to present mitigating evidence during the sentencing phase of his trial.

"[23] Additionally, the Sixth Circuit held that the Tennessee Court of Criminal Appeals decision constituted "an unreasonable application of the clearly established law".

[29] Additionally, Chief Justice Rehnquist wrote that in order to presume prejudice under the standards set forth in United States v. Cronic,[30] an attorney's failure to subject a case to adversarial scrutiny "must be complete.

[33] Finally, Chief Justice Rehnquist wrote that the attorney's choice to waive his closing argument was a "tactical decision about which competent lawyers might disagree.

"[34] Justice John Paul Stevens wrote a dissenting opinion in which he argued that Cone's attorney "entirely fail[ed] to subject the prosecution's case to meaningful adversarial testing.

[41] In a 2007 opinion, the Sixth Circuit reconsidered whether the prosecution violated Cone's rights to due process under the Fourteenth Amendment[42] by withholding police reports and witness statements that potentially could have corroborated his claims about the effects of his drug use.

"[47] Justice Stevens noted that "the quantity and the quality of the suppressed evidence lends support to Cone’s position at trial that he habitually used excessive amounts of drugs, that his addiction affected his behavior during his crime spree, and that the State’s arguments to the contrary were false and misleading.