In the 1995 case of Juan Melendez v. United States, Melendez was convicted for conspiracy to distribute and possession with intent to distribute five kilograms or more of cocaine. The main issue in this case revolved around whether a police officer's testimony about a co-conspirator's out-of-court statements violated the Confrontation Clause because the co-conspirator did not testify at trial. The Supreme Court held that it did not violate the clause as long as there is sufficient non-hearsay evidence linking the defendant to the conspiracy. Furthermore, they ruled that even if such violation occurred, it would be considered harmless error given other overwhelming evidence against Melendez including surveillance footage and testimonies from multiple witnesses who were part of or had direct knowledge about his drug trafficking activities.

In the dissenting opinion for Juan Melendez v. United States, it was argued that the majority's decision to uphold Melendez's conviction despite evidence of prosecutorial misconduct undermined the integrity of the judicial process. The dissenting justices believed that by allowing a prosecutor to knowingly use perjured testimony and then fail to correct it, they were essentially endorsing an unfair trial. They contended that this not only violated Melendez’s due process rights but also damaged public confidence in courts' ability to deliver justice fairly and accurately. Furthermore, they disagreed with the majority's view on materiality standard application; instead asserting that any reasonable likelihood of affecting judgment should be enough ground for reversal rather than proving beyond reasonable doubt its effect on outcome.