In Darden v. Florida, 1976, the U.S Supreme Court examined whether a prosecutor's improper comments during closing arguments violated the defendant's constitutional rights. The case involved William Lloyd Darden who was convicted of murder and sentenced to death in Florida state court. During his trial, the prosecutor made inflammatory remarks about Darden which were deemed inappropriate by defense counsel but allowed by the presiding judge. On appeal to the Supreme Court, it was argued that these comments denied him a fair trial as guaranteed under both Fifth and Fourteenth Amendments' due process clauses. The Supreme Court upheld Darden’s conviction with a 5-4 majority ruling that while such prosecutorial misconduct could potentially prejudice jurors against defendants and violate their right to impartial trials; in this particular instance they did not deprive him of a fair trial because there was overwhelming evidence pointing towards his guilt regardless of those statements.

In the dissenting opinion for Darden v. Florida, Justice Brennan argued that the prosecutor's inflammatory comments during closing arguments violated Darden's constitutional rights and required a new trial. He contended that such remarks could have unduly influenced the jury by appealing to their emotions rather than focusing on factual evidence. Furthermore, he criticized the majority for failing to establish clear standards regarding prosecutorial misconduct in order to prevent future violations of defendants' rights. Justice Brennan also disagreed with how harmless error analysis was applied in this case, believing it should not be used as an excuse to overlook serious errors or misconduct during trials.