In the case of Joseph E. Corcoran v. Mark Levenhagen, Superintendent, Indiana State Prison (2009), the U.S Supreme Court addressed an appeal from a death row inmate who claimed his constitutional rights were violated when he was not allowed to present mitigating evidence during his sentencing hearing. The court ruled in favor of Corcoran and remanded the case back to lower courts for further proceedings. Corcoran had been convicted on four counts of murder and sentenced to death by an Indiana state court. He appealed this decision arguing that he should have been allowed to present evidence about his mental health at sentencing as it could have potentially reduced his sentence or eliminated capital punishment altogether. The Supreme Court agreed with him stating that under the Eighth Amendment's prohibition against cruel and unusual punishment, a defendant has a right to introduce mitigating circumstances during their sentencing phase in capital cases.

In the dissenting opinion for Joseph E. Corcoran v. Mark Levenhagen, Superintendent, Indiana State Prison (2009), Justice Scalia argued that the Court of Appeals had not erred in its decision to deny habeas relief to Corcoran on his claim that he was denied a fair trial due to prosecutorial misconduct and ineffective assistance of counsel. He contended that the prosecutor's comments during closing arguments did not amount to misconduct because they were based on evidence presented at trial and did not misrepresent or distort any facts. Furthermore, he asserted that Corcoran's defense attorney provided effective representation by thoroughly cross-examining witnesses and presenting an alternative theory of the crime. Therefore, according to Justice Scalia, there was no reason for federal courts to intervene in this state court conviction.