In the Satterwhite v. Texas case of 1987, the U.S Supreme Court ruled that a psychiatrist's testimony at sentencing violated a defendant's Sixth Amendment right to counsel because it was based on an uncounseled pretrial psychiatric examination ordered for competency purposes. The defendant, Leonel Torres Herrera (Satterwhite), had been convicted of murder and sentenced to death in Texas state court. During his trial, Dr. James Grigson testified about Satterwhite’s future dangerousness based on an earlier evaluation conducted without his attorney present. The Court held that this constituted a violation of the Sixth Amendment as it allowed evidence from an uncounseled interview with a mental health expert into penalty proceedings in capital cases.

In the dissenting opinion for Satterwhite v. Texas, Justice Marshall argued that the majority's decision to allow harmless error analysis in cases involving violations of a defendant's Sixth Amendment right to counsel was fundamentally flawed. He contended that this approach undermined the importance and purpose of this constitutional guarantee by permitting convictions obtained through methods that are constitutionally suspect. Furthermore, he criticized the majority’s application of harmless error analysis as inconsistent with previous Supreme Court precedents which held such errors should be considered harmful per se unless they did not contribute to the conviction or sentence imposed on a defendant. In his view, there was no way to determine beyond reasonable doubt whether admission into evidence at sentencing phase of psychiatric testimony taken without counsel present had an impact on death penalty verdict given its potential influence over jury’s perception about defendant’s future dangerousness – one key factor in capital sentencing decisions under Texas law.