Leon, 1984). The dissenting opinion was expressed by Justice Brennan, joined by Justice Marshall. Their concerns were that the majority opinion could be the beginning of the exclusionary rule's demise. Brennon had observed that the Court had slowly begun to let more things run afoul of the Fourth Amendment, and that the "good faith" exception directly contradicted the Fourth Amendment. He also argued that it may appear that the Court can cherry-pick what evidence it allows in the interest of securing a conviction. (United States v. Leon, 1984) The concurring opinion was given by Justice Blackmun. He agreed with the majority opinion that the rule of exclusion is valid as long as the officer and magistrate act in "good faith", but he was keen to emphasize that it is not a rule to be taken at face value. slight, that it may change depending on how cases such as this are handled in the future. (United States v. Leon ,