545 U.S. 374 (2005)
- During the penalty phase, the prosecutor sought to prove that the murder was committed in the course of another felony, by torture, and that petitioner had a significant violent felony conviction history.
- Inter alia, the Court held that counsel had a duty to make all reasonable efforts to learn what they could about the offense, including obtaining the prior conviction file to discover any mitigating evidence and to anticipate the aggravating details.
- Given that defense counsel had notice of the death penalty, the conviction file showed prior rape and assault convictions, and the file was a readily accessible public document, the lawyers were deficient in failing to examine that file.
- Without this information, a convincing residual doubt argument impossible.
- Thus, the Commonwealth courts were objectively unreasonable in concluding that counsel could reasonably decline to make any effort to review the file.
- Moreover, the file also included mitigation leads that no other source suggested and would have prompted further investigation.
- The undiscovered mitigating evidence might well have influenced the jury's appraisal of the petitioner's culpability.
The Court reversed the judgment of the circuit court.
Recommended Supplements for Criminal Procedure Criminal Procedure: Examples & Explanations, Sixth Edition
Emanuel Law Outline: Criminal Procedure