In the case of Marlon Latodd Howell, aka Marlon Cox v. Mississippi (2004), Howell was convicted for capital murder and sentenced to death in a state court in Mississippi. The Supreme Court of Mississippi affirmed his conviction and sentence on direct appeal, rejecting his claim that he received ineffective assistance from trial counsel due to their failure to investigate and present mitigating evidence during the penalty phase of his trial. After exhausting state post-conviction remedies, Howell filed a federal habeas corpus petition arguing again that he had received ineffective assistance from counsel at sentencing. However, both the District Court and U.S Circuit Court rejected this argument as they found no reasonable probability that additional mitigation evidence would have changed the outcome of his sentencing proceeding.

In the dissenting opinion for Marlon Latodd Howell v. Mississippi, Justice John Paul Stevens argued that the defendant's Sixth Amendment right to a fair trial was violated due to prosecutorial misconduct. He contended that the prosecutor had improperly influenced the jury by introducing evidence of Howell's prior convictions and suggesting they indicated his propensity for violence, which is not permissible under Mississippi law or federal constitutional standards. Furthermore, he criticized how this information was presented during closing arguments rather than in its proper context during cross-examination or rebuttal testimony. This timing prevented defense counsel from effectively challenging its relevance and prejudiced Howell’s case unfairly according to Justice Stevens. He also expressed concern about racial bias influencing sentencing decisions in capital cases like this one where an African American man was sentenced to death by an all-white jury.