I’m delighted to be guest-blogging about my forthcoming article, “The Due Process Exclusionary Rule.” Many thanks to Eugene and the other conspirators for inviting me!

In this first post, I’d like to say a few introductory words about why this is an unusually important time to be thinking about the exclusionary rule. The short answer is this: the rule’s fundamental characteristics — and perhaps even its existence — are up for grabs in a way that they haven’t been for at least 30 years. To see why, we need some historical context.

The Court’s single most important exclusionary rule decision was probably Mapp v. Ohio (1961). Mapp held that suppression of evidence is necessary not only when federal officers violate the Fourth Amendment, but also when state and local police do so. The decision was a bombshell, and its language was sweeping: “We hold that all evidence obtained by searches and seizures in violation of the Constitution is, by that same authority, inadmissible in a state court.” The Court appeared to be saying evidence obtained by violating the Fourth Amendment could never see the inside of a courtroom. Without this rule, the Court feared, the Fourth Amendment would be reduced to “a form of words.” Only exclusion, it seemed, could deter police from violating the Fourth Amendment.

But evidence that is obtained illegally is still evidence, and the people it implicates could be guilty of serious crimes. So it is no surprise that the exclusionary rule has always been controversial. As then-Judge (later Justice) Benjamin Cardozo lamented in 1926, “The criminal is to go free because the constable has blundered.” Somehow, the exclusionary rule transforms two illegal acts into zero convictions. Acknowledging that oddity, Judge Henry Friendly wrote a classic article in 1965 contending that the rule should apply only where the police have egregiously violated the Fourth Amendment — not when they have committed “slight” or “unintentional” errors.

Judge Friendly’s “good faith” proposal has been gaining ground ever since its publication. In a 1983 case, the Court specifically requested argument on whether to accept a general good-faith exception. After declining to do so, the Court soon adopted a narrower good-faith exception applicable only when the police have obtained a warrant. In the decades that followed, the Court added new good-faith exceptions for other contexts.

The pace of change has picked up during the Roberts Court, particularly after the Court’s 5-4 decision in Herring v. United States. Writing for the Court, Chief Justice Roberts repeatedly cited the article that his former boss, Judge Friendly, had published over 40 years earlier. Viewing the rule as a prudential doctrine, the Court reasoned that it should apply only where its benefits outweigh its costs. Unless the police have engaged in “systemic error or reckless disregard of constitutional requirements, any marginal deterrence does not ‘pay its way.’” Taking Herring and other Roberts Court decisions at their word, courts are increasingly conducting a cost-benefit analysis before applying the exclusionary rule.

So courts face an important question: should the good-faith principle become the rule, and suppression the exception? The rest of my posts will try to provide an answer.

The views set forth in these posts are the personal views of the author and do not necessarily reflect those of the law firm with which he is associated.