In the case of Henry Jose Espinosa v. Florida, 1991, Espinosa was convicted for first-degree murder and sentenced to death by a Florida state court. The Supreme Court reviewed whether the trial court's failure to instruct the jury on an essential element of the crime violated his due process rights under the Fourteenth Amendment. It also examined if this error could be considered harmless beyond a reasonable doubt since there was overwhelming evidence against him regardless of this omission in instruction. The Supreme Court held that such an error does not automatically require reversal of conviction as it may be deemed harmless if found beyond a reasonable doubt that it did not contribute to verdict obtained. However, they remanded back to lower courts for further proceedings consistent with their opinion because they were unable to determine from record whether or not this specific instructional mistake had been harmless.

In the dissenting opinion for Henry Jose Espinosa v. Florida, it was argued that the majority's decision to uphold Espinosa's death sentence despite a flawed jury instruction on mitigating circumstances was incorrect. The dissenting justices believed that this error had a substantial and injurious effect or influence in determining the jury’s verdict, which should have warranted reversal of his conviction under established precedent. They contended that by failing to properly instruct jurors about their duty to consider all potential mitigating evidence before deciding whether to impose capital punishment, Espinosa's constitutional rights were violated as he did not receive fair consideration for a life sentence instead of death penalty. Furthermore, they criticized the majority for setting an alarming new standard where such serious errors could be dismissed as harmless without any clear guidelines or analysis demonstrating why this particular mistake didn't affect Espinosa’s sentencing outcome.