The exclusionary rule, with, and without its myriad exceptions, represents the Supreme Court’s attempt to grapple with the two competing interest. First, the exclusionary rule aims to protect individual liberty interests protected by the Fourth Amendment. This liberty interest results in the social cost to society of criminals potentially going free. Second, the exceptions to the exclusionary rule exist to ensure that the police are able to protect society by gathering evidence of wrongdoer. This governmental power results in the social cost of police violating the Fourth Amendment, and potentially engaging in overbearing investigative techniques. The Court’s jurisprudence stretching from Mapp v. Ohio, to United States v. Leon, to Michigan v. Bryant, represents a shift. In the earlier cases, the fear of the social costs from the governmental power exceeded the fear of social costs from individual liberty interests. Deference was given to the individual liberty interests, and skepticism was applied to the state’s interest. Under this framework, the individual will usually win, and the government will usually lose. However, in the years following Mapp, leading to Leon, this social cost calculus flipped, as the Fourth Amendment has been carved up like a Jack-o’-lantern–with jagged cuts, grotesque features, and a hollow, carved-out vacuous interior. Under our modern jurisprudence, the fears of criminals going free exceeds the fear of improper interrogation techniques. Deference is given to the state’s interest in providing for collective security, and skepticism is given to the individual liberty interest. This jurisprudential transition is largely informed by competing views of social cost of individual liberty and government power. How the Court has changed its approach is based on this calculus.

Perhaps the most eloquent expression of the exclusionary rule whereby the individual liberty interest trumps is Justice Holmes’s dissent in Olmstead v. United States dissent: “We have to choose, and for my part I think it a less evil that some criminals should escape than that the Government should play an ignoble part.”#
Find quotes from Mapp and Weeks
In dissent in Seguar v. United States, Justice Stevens noted that the Court is “acutely aware of the social costs” of exclusion of “unconstitutionally obtained evidence.”# In these cases, “[o]nly the most compelling reason could justify the repeated imposition of such costs on society.” The reason, “is to prevent violations of the Constitution from occurring.”# This reasoning–circular in the sense that unconstitutionally obtained evidence is excluded to avoid obtaining evidence in violation of the Constitution–advances deference to the individual liberty interest (freedom form unconstitutional searches), and is skeptical of the costs to society (of failing to convict defendants with tainted evidence).

However, this position became that of the minority. Stevens’s understanding of social cost, throughout the 1970s and 1980s was slowly chipped away. In a series of opinions in the late 1970s and early 1970s, several Justices focued on the “social costs” occasioned by the exclusionary rule. In Stone v. Powell, Chief Justice Burger noted that, “[t]he Court’s opinion today [applying the exclusionary rule] eloquently reflects something of the dismal social costs occasioned by the rule.”# In United States v. Janis, Justice Blackmun remarked that the exclusionary rule was not extended to forbid the use in the federal civil proceedings of evidence illegally seized by state officials, since the likelihood of deterring unlawful police conduct was not sufficient to outweigh the societal costs imposed by the exclusion.”# Again, in Brewer v. Williams, Chief Justice Burger lamented that “Against this background, it is striking that the Court fails even to consider whether the benefits secured by application of the exclusionary rule in this case outweigh its obvious social costs.”# In Rakas v. Illinois, Justice Rehnquist wrote “[e]ach time the exclusionary rule is applied it exacts a substantial social cost for the vindication of Fourth Amendment rights. Relevant and reliable evidence is kept from the trier of fact and the search for truth at trial is deflected.”# In Illinois v. Gates, Justice Rehnquist, wrote  “Because of the inherent trustworthiness of seized tangible evidence and the resulting social costs from its loss through suppression, application of the exclusionary rule has been carefully ‘restricted to those areas where its remedial objectives are thought most efficaciously observed.’”#

In United v. Leon, the Court introduced the good faith exception to the exclusionary rule.# This change was closely tied to a shift in thinking about the attendant social costs of the Fourth Amendment interests, as compared to the social costs of the state’s interest in collecting evidence.  For the majority, Justice White lamented that the “substantial social costs exacted by the exclusionary rule for the vindication of Fourth Amendment rights have long been a source of concern.” Under Leon, evidence seized in violation of the Constitution–but obtained in good faith reliance that the search was lawful–would be admissible in trial. Members of the Court, long unsatisfied with the  attendant social costs of criminals going free–and the resulting crime–were no longer willing to tolerate the individual’s social costs, which now exceeded the government’s social costs. Now, deference went to the state’s interests, and skepticism went to the individual’s interest. Though not all were persuaded by this shift in deference and skepticism.

Justice Brennan, in classic fashion, quickly dispensed with this social cost reasoning. Labelling the majority’s opinion a “bit of judicial stagecraft,” he finds “while the sets sometimes change, the actors always have the same lines.” The Court’s opinion in Leon follows what Brennan labels a “well-rehearsed pattern.” This pattern, is simply a reconceputalization of social cost. With Leon, and its predecessors, the Court now puts more weight on the social costs from defendants going free–in the form of lost convictions–than on the social costs of unconstitutionally obtaining evidence. To Brenann, this latter social cost is greater. To the majority, the former social cost is greater. Brennan would give more deference to the individual, and skepticism to the state’s interest. The majority, in reverse, shows deference to the state’s interest, and is skeptical of the individual’s liberty claim.

With the social costs assigned as they are, Brennan quips, “one might have predicted with some assurance how the present case would unfold.” First, Brennan notes that “there is the ritual incantation of the ‘substantial social costs’ exacted by the exclusionary rule, followed by the virtually foreordained conclusion that, given the marginal benefits, application of the rule in the circumstances of these cases is not warranted.” Numerous cases, both before, and after Leon, follow Brennan’s script.# Just this past term, Justice Alito, for 7 members of the Court, was not willing to exclude evidence when “the police conduct a search in objectively reasonable reliance on binding appellate precedent”; to do so “deters no police misconduct and imposes substantial social costs.”#  Alito described the exclusionary rule as a “bitter pill” that must “society must swallow . . .  when necessary, but only as a ‘last resort.’” “For exclusion to be appropriate, the deterrence benefits of suppression must outweigh its heavy [social] costs.”#

Yet, Brennan’s rhetoric is stronger than his reasoning. Both opinions are simply going through the motions, and reciting incantations; the difference, however is which social cost is perceived be greater. To paraphrase Brennan–under his own view of the Fourth Amendment–there is the ritual incantation of the ‘substantial social costs’ exacted by unconstitutional acquisition of evidence, followed by the virtually foreordained conclusion that, given the marginal benefits, application of the rule in the circumstances of these cases is warranted–as to introduce the evidence in Court would fail to provide sufficient deterrence for future police misconduct. Brennan concludes, “Upon analysis, however, such a result cannot be justified even on the Court’s own terms.” The same could be said for Brennan’s analysis, which simply allocates social cost differently. Dichotomies of “liberal” and “conservative” views ultimately boil down to which social cost a Justice sees as greater–that of individuals, or that of the government. Once that allocation is made, Justice Brennan is apt to note that the conclusion is “virtually foreordained.”