The Supreme Court in Thornell v. Jones, 602 U.S. ___ (May 30, 2024), reversed the grant of habeas corpus relief by the Ninth Circuit Court of Appeals to Arizona death row inmate Danny Jones on a claim of ineffective assistance of counsel at sentencing. Jones was sentenced to death for three murders with aggravating circumstances factors of multiple murder, murder for pecuniary gain, “especially heinous, cruel or depraved” murders and murder of a young child. The Supreme Court found that the Ninth Circuit had departed from Strickland v. Washington's prejudice inquiry in at least three ways: (1) "it failed adequately to take into account the weighty aggravating circumstances in this case"; (2) it applied a "clearly unsound" rule prohibiting a court considering a Strickland claim from "assessing the relative strength of expert witness testimony," e.g., comparing defense expert testimony with a contrary opinion of a prosecution expert in order to determine what weight to accord to the defense expert; and (3) finding the District Court erred by attaching diminished persuasive value to Jones’s mental health conditions because it saw no link between those conditions and Jones’s conduct when he committed the three murders. This last mistake by the Ninth Circuit was based on its misinterpretation of Eddings v. Oklahoma, 455 U. S. 104 (1982). The Supreme Court clarified that while Eddings held that a sentencer may not “refuse to consider . . . any relevant mitigating evidence” (Id., at 114), it did not hold that a sentencer cannot find mitigating evidence unpersuasive.
When the Strickland prejudice analysis is properly applied, Jones is not entitled to habeas relief: "Most of the mitigating evidence Jones presented at the federal evidentiary hearing was not new, and what was new would not carry much weight in Arizona courts. Conversely, the aggravating factors present here are extremely weighty. As a result, there is no reasonable probability that the evidence on which Jones relies would have altered the outcome at sentencing."