In the case of Paul Caspari, Superintendent, Missouri Eastern Correctional Center et al. v. Christopher Bohlen (1993), the U.S Supreme Court ruled on whether a state court's decision could be considered "contrary to" or an "unreasonable application of" clearly established federal law as determined by the Supreme Court itself. The dispute arose when Bohlen was convicted for first-degree sexual abuse and sentenced to life imprisonment without parole eligibility for 50 years in Missouri state court. He appealed his sentence arguing that it violated his Eighth Amendment rights against cruel and unusual punishment because he was a minor at the time of offense. The Federal District Court rejected this claim but granted habeas corpus relief based on its conclusion that Bohlen’s due process rights were violated during sentencing phase since jury instructions did not require unanimity about which underlying felony supported conviction for capital murder. However, upon reaching Supreme Court, it reversed lower courts' decisions stating they had misapplied Teague v Lane rule which prohibits retroactive application of new constitutional rules in cases finalized before those rules are announced unless exceptions apply. It held that no such exception applied here as there wasn't any 'watershed' change in law nor did non-unanimous verdict lead to fundamental unfairness undermining accuracy or reliability.

In the dissenting opinion for Caspari v. Bohlen, Justice Blackmun argued that the majority's decision was inconsistent with previous rulings and violated principles of fairness and justice. He contended that retroactive application of new rules should be allowed when they significantly affect a defendant's opportunity to avoid wrongful conviction or enhance fact-finding accuracy in criminal trials. The majority’s rule, he believed, would prevent courts from applying such important changes to cases on collateral review even if those changes were announced before a petitioner’s conviction became final. This could lead to unjust results where defendants are denied benefits of significant legal developments simply because their convictions preceded these developments by mere days or weeks. Furthermore, he criticized the majority for failing to provide clear guidance about what constitutes an "old rule" versus a "new rule," leading potentially to confusion among lower courts.