In the case of Bobby Lee Holmes v. South Carolina, 2005, the U.S. Supreme Court ruled in favor of Holmes and overturned a decision by the South Carolina Supreme Court that had upheld his conviction for murder. The issue at hand was whether or not it was constitutional to exclude evidence from a third party when there is strong forensic evidence linking the defendant to the crime scene. In this case, Holmes wanted to introduce evidence suggesting another man committed the crime but was barred from doing so due to state rules barring such testimony if forensic evidence strongly suggested guilt on part of defendant. The U.S. Supreme Court held that these rules violated Holmes' right under Due Process Clause as they were arbitrary and disproportionate with respect to their purpose - preventing confusion among jurors about issues unrelated to guilt or innocence; thus denying him a fair opportunity for presenting defense.

In the dissenting opinion for Bobby Lee Holmes v. South Carolina, Justice Alito disagreed with the majority's decision to overturn a state rule that limited a defendant's ability to present evidence of third-party guilt if the prosecution has introduced forensic evidence that strongly supports a guilty verdict. He argued that this rule was not unconstitutional and did not violate due process rights because it only applied when there was strong forensic evidence against the defendant, which he believed would make any third-party guilt theory implausible or irrelevant. Furthermore, he contended that states should have discretion in setting their own rules about admissibility of certain types of evidence as long as they do not infringe on constitutional rights.