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Sherry F. Colb

Excluding Illegally-Obtained Evidence and the Doctrine of Double Effect


Wednesday, November 25, 2009

Every time I teach my course in criminal procedure, I am struck by the diametrically opposed perspectives of those Justices on the Supreme Court who have favored the suppression of evidence obtained in violation of the Fourth Amendment, and those who have opposed it. This opposition extends beyond the Court to the scholars and attorneys who debate about the Fourth Amendment as well. Core supporters find suppression absolutely essential to justice, while opponents find it offensive and believe in limiting its application as much as possible or eliminating it altogether.

It is unusual – outside the context of religiously-tinged subjects like abortion – to find such "pure" and unadulterated ideological disagreement, where each side believes that the other's position is not only wrong but disgusting. I will suggest here that a doctrine with religious origins – the Double Effect Doctrine, originally promulgated by the Catholic Church and then widely applied within moral philosophy – may help illuminate the division between the opposing camps on the question of Fourth Amendment suppression.

What is the Double Effect Doctrine?

The Doctrine of Double Effect (DDE) holds that intentionally and directly causing harm as a means of accomplishing a positive outcome is morally distinct from intentionally and directly bringing about the positive outcome while knowingly causing the same harm as an undesired side effect. Whether one may permissibly bring about such undesired effects depends upon whether they are outweighed by other, desired effects. Such weighing or balancing of effects, however, occurs only after we ascertain that no harm is actually intended.

Consider the following example. Oceania is at war with Eurasia. To help win the war, Oceania decides to bomb a critical munitions plant in Eurasia. The Oceania official who makes this decision knows that there are always three civilians inside the munitions plant. He wishes the civilians were not there, but there is no way to warn them or otherwise evacuate the plant without alerting the enemy to activate its air defenses. The Oceania official bombs the plant, and three civilians die. Assume that the harm in bloodshed averted by bombing the plant is greater than the harm inflicted by the bombing. Many would view the official's action as justified.

Now, assume that, instead, Oceania simply decides to kill three civilians who live in an apartment located inside the plant – because the loss of these people will demoralize the officials in charge of the Eurasia war effort and lead to a quicker end to the war (and a corresponding substantial reduction in bloodshed). Learning that the three people are currently inside the plant, the relevant Oceania official decides to carry out the assassinations by bombing the building. The effort succeeds. All three civilians die.

The ultimate goal in both examples is the same: to disable Eurasia's war effort. The known outcome in loss of life is also the same: three civilians will die. And the method of carrying out the project in question is the same: bombing the munitions plant. Yet the DDE treats these scenarios as distinct. In the first case, the loss of life is an unintended and tragic side-effect of the intentional destruction of property. If it were possible to destroy the plant without killing anyone, the Oceania official would have done so, but the loss of life, given the particular contingencies, was unavoidably tied to the destruction of the property in question. The three civilians, then, were "collateral" victims, rather than intended victims.

In the second case, by contrast, the very purpose of the bombing was to kill the three civilians. If there had been a known time during which the building was empty, then the Oceania official would have avoided, rather than selected, that time for bombing.

Under the DDE, the second action is morally impermissible, while the first action is permissible (or might be, if the harm avoided by bombing the plant truly outweighs the civilian deaths incidentally inflicted). It is, on this theory, simply wrong to kill three civilians deliberately, even if the killing would accomplish a greater good – the sparing of many more innocent lives. One cannot use an innocent person – by intentionally killing him or her – to help others survive. This is why, for example, it is morally wrong to take a healthy person and remove his vital organs in order to distribute them to five people who need various organs to survive.

According to the DDE, however, one may embark on justifiable activities that have, as incidental effects, the infliction of harm, provided that the harm avoided outweighs the harm inflicted. (Some theorists argue about whether this further requirement of proportionality is properly characterized as part of the DDE itself or a stand-alone moral requirement, but that question need not concern us here.) Once we are no longer acting with the intention to bring about a result, in other words, it becomes acceptable for us to compare the consequences of acting with the consequences of not acting (or of acting in a different manner), and to choose the path that maximizes the beneficial consequences.

The Fourth Amendment Exclusionary Rule

Now that I have given you a flavor of the DDE's approach to moral philosophy, I will describe the Fourth Amendment exclusionary rule. The Fourth Amendment itself bars the government from performing unreasonable searches and seizures. As the Supreme Court has interpreted this prohibition, it serves to protect people's privacy from inappropriate police surveillance and investigation, along with protecting their liberty (from improper arrest) and property (from unwarranted removal). When people complain of police having entered their home without probable cause to look for evidence, they are complaining of an "unreasonable search."

If police disregard the Fourth Amendment and carry out unreasonable searches and seizures, the victims of such actions may, in theory, sue the police for violating their constitutional rights. But except in cases of excessive force leading to serious injury, successful Fourth Amendment lawsuits are rare. Guilty people who have suffered Fourth Amendment violations make unsympathetic plaintiffs, while innocent people who have been unfairly targeted for searches and seizures typically have not suffered sufficient damages to justify the hassle and expense of going to court. Thus, in reality, the most common enforcement mechanism against Fourth Amendment violations is the exclusionary rule.

Under the exclusionary rule, when police violate the Fourth Amendment and obtain evidence as a result, the victim of the violation can suppress the evidence at his or her criminal trial. This means that prosecutors may not introduce the illegally-obtained evidence to help prove that the defendant – whose rights police violated to get that evidence – is guilty of the charged offense or offenses.

The exclusionary rule has long been an extremely controversial approach to motivating Fourth Amendment compliance by police. One skeptical perspective, to paraphrase Justice Cardozo's language, complains that under the exclusionary rule, the criminal goes free just because the constable has blundered. It seems outrageous, on this view, that a police violation of the Fourth Amendment – an injustice, to be sure – should be compounded with another injustice: the release, without conviction and punishment, of a person who violated the criminal law. If the suppression of illegally-obtained evidence is enough to make the conviction of a guilty defendant impossible, as it sometimes is, then the suppression remedy brings about a miscarriage of justice.

Strong defenders of the exclusionary rule, both on and off the Supreme Court, have taken a very different approach. Justice William J. Brennan, for example, said the following:

[S]ome criminals will go free not, in Justice (then Judge) Cardozo's misleading epigram, "because the constable has blundered," but rather because official compliance with Fourth Amendment requirements makes it more difficult to catch criminals. Understood in this way, the Amendment directly contemplates that some reliable and incriminating evidence will be lost to the government; therefore, it is not the exclusionary rule, but the Amendment itself, that has imposed this cost.

This position holds that, in choosing to have a Fourth Amendment, our constitutional system necessarily accepts that limiting police investigative latitude, as a restraint on searches and seizures does, will reduce the number of guilty people we can successfully apprehend and punish. Stated differently, the Fourth Amendment right against unreasonable searches and seizures carries an understood cost: Some people who have committed crimes will remain undiscovered and thus get away with their offenses, because police may not do "everything it takes" to find all of the criminals.

If we acknowledge that an unreasonable search or seizure should never have taken place, as a matter of Fourth Amendment law, then – say some defenders of exclusion – the suppression of any resulting evidence simply restores the status quo ante that the Fourth Amendment itself contemplated: We do not have access to evidence that surfaced only because of police disregard for the Fourth Amendment. Had the police acted as they should have, we still would not have access to the evidence. In this narrative, the exclusionary rule is not the source of the cost; rather, the constitutional prohibition against the search or seizure is the source of the cost.

The DDE and the Exclusion of Evidence

The DDE offers a new way of looking at the question whether the release of guilty criminals is a cost of the exclusionary rule, or whether it is a cost of the Fourth Amendment itself. Most people on either side of the debate can likely agree that if police always obeyed the dictates of the Fourth Amendment, then at least some of the criminals we currently "catch" due to unreasonable searches and seizures would never have been caught. That is, the Fourth Amendment is not a cost-free privacy protection; we understand that restraining police has the undesirable consequence of preventing some criminals from being caught and removed from free society. Under the DDE, this does not make the Fourth Amendment wrong, because we may legitimately decide that some level of undetected (and unstopped) crime is worth the corresponding gain in security and liberty that accompanies a society in which the government abides by the Fourth Amendment.

When we as a society choose to restrain the police with a Fourth Amendment, we do so with the intention of enhancing our privacy and liberty from government incursion. We do not aim thereby to cloak the guilt of criminals and prevent their apprehension, but we understand that this is an incidental – undesired – effect of the security that we seek. If we assume that privacy and liberty for the large collective of innocent people is worth the cost in freedom retained by some undeserving and dangerous people, then the choice to bar unreasonable searches and seizures is a morally defensible or justifiable choice, notwithstanding the collateral damage that it inflicts – in the form of the failure to capture and punish guilty people.

One can thus think of the failure to catch and punish guilty people as comparable to the three people who die in the first bombing of the munitions plant: No one wants those people to escape justice/die, but their escape/death is a virtually certain (though contingent) consequence of a cost-justified decision to protect people's privacy/destroy the plant.

Now consider the exclusionary rule. Though its application results in the same harm contemplated by the Fourth Amendment, the harm is now direct, rather than incidental. We are no longer prohibiting the police from performing unreasonable searches and seizures with the knowledge that guilty people will remain free as a result; we are directly subverting the truth-finding process in a criminal case by taking evidence that we already have, and refusing to allow the prosecution to present that evidence to the jury. If the defendant cannot be prosecuted successfully as a result, then this undeserved windfall is no longer an incidental side effect of Fourth Amendment compliance; it is the direct effect of the exclusionary rule. Had the violation never taken place, of course, the freedom of the undiscovered offender would have been a side-effect of the Fourth Amendment. But it did take place, and now suppression is a deliberate choice.

One important point to make here is that any serious Fourth Amendment regime must include some enforcement mechanism. Having a Fourth Amendment does not itself change police behavior or protect security from unreasonable searches and seizures, unless there are consequences for violations. One kind of consequence is civil liability, and people do sometimes successfully sue for monetary damages for Fourth Amendment violations. If such lawsuits had their intended effect and deterred Fourth Amendment violations, then they too would be responsible for cloaking the misdeeds of some serious offenders and thereby impeding the criminal prosecution and incarceration of some very bad people. Again, however, the purpose of deterrence would not be to shield the guilty from apprehension; the goal would be to enhance privacy and security, and the incidental and undesired collateral effect would be to shield the guilty. Compensating a victim of a Fourth Amendment violation accordingly does not directly undermine justice in a criminal case; if it impedes justice, it does so only as a side-effect of deterring future violations.

The exclusionary rule is thus, from the DDE perspective, quite different from a civil suit alternative, just as it is quite different from the Fourth Amendment itself. It intentionally impedes a criminal prosecution by keeping probative evidence from a jury and does so as a means of deterring future violations.

If it is unjust to free a guilty person, in other words, then the exclusionary rule directly perpetrates an injustice as a way of maximizing privacy and liberty, just as the killing of the three civilians in our earlier second example directly perpetrates homicide as a way of preventing future deaths.

A Fanciful Example to Illustrate the Point

Beyond the failure to catch and punish offenders, the Fourth Amendment carries another foreseeable cost: Police will sometimes fail to detect an ongoing act of violence that would otherwise have come to light. As a result, some people who would otherwise have been rescued from ongoing substantial bodily harm and death will now suffer and die instead.

We know that this is a cost of limiting police surveillance, and we choose to live with that cost. If police had cameras installed in every home, they could intervene much more effectively in ongoing domestic violence, child sexual abuse, and myriad other criminal enterprises. Indeed, such totalitarian surveillance might deter aspiring perpetrators from engaging in their abhorrent criminal conduct in the first place. Notwithstanding this collateral, unintentional, and deeply regrettable cost in foregone security from miscreants, we still regulate and restrain police invasions of privacy.

Assume, however, that a police officer breaks into a home without probable cause, on the basis of a mere "hunch" – the sort of intuition that will ordinarily lead to inappropriate invasions of privacy and that fails to meet the legal standards of the Fourth Amendment. After breaking in, the officer finds inside the home a two-year-old boy who is tied to a bed and dying of dehydration and starvation. What should the officer do, given what she has learned?

It is difficult to imagine anyone arguing that the officer should leave the house and forget what she has seen, thus allowing the toddler to die. The right thing to do is clear: the officer should untie the child and bring him to a hospital for intravenous fluids and other necessary medical intervention. The officer should save the boy's life.

Obeying the Fourth Amendment's dictates would have been morally justified despite the fact that it would have (incidentally and, from the particular police officer's perspective, unknowingly) led to the child's death, but that does not mean that the officer would be justified, after seeing the child, in leaving the house and permitting him to die. Complying with the Fourth Amendment in every case has the incidental effect of failing to rescue the child; ignoring the child because he was found only as a result of an illegal search directly disregards the child's need to be rescued. Such disregard, of course, would represent the logical conclusion of an exclusionary rule that demanded forgoing any benefits that accrue as a result of a Fourth Amendment violation.

When an adherent of the Fourth Amendment exclusionary rule argues that there is simply no difference between avoiding violations, on the one hand, and excluding evidence obtained through violations, on the other, he or she ignores this important insight of the DDE and suggests that leaving the child to die would be no different from effectively deterring Fourth Amendment violations that would have saved his life. Such a suggestion is counter-intuitive, to say the least.

Exclusion of Evidence Might Still be Warranted

I have argued here that the DDE can be used to make a case for distinguishing between the Fourth Amendment and the exclusionary rule. Importantly, I want to make clear that I am not arguing that the exclusionary rule is an unjustifiable way of enforcing the Fourth Amendment's prohibition against unreasonable searches and seizures.

Unlike intentionally killing three people, intentionally releasing a guilty person could conceivably be justifiable as a means of serving a greater good. In other words, it may be worse to release a guilty person on purpose, through exclusion of evidence, than it is to do so as an incidental effect of the Fourth Amendment, but it may nonetheless be morally and legally justifiable to do so. Indeed, using the release of guilty people as a means of motivating police to respect privacy in the future might be just what the doctor ordered, if other remedies have not shown much promise over the years.

Significantly, even the more conservative wing of the current Supreme Court has not (yet) said that we should abolish the exclusionary rule altogether. Therefore, even some who find the impact of exclusion extremely costly (and who – consistent with the DDE – understand those costs to be properly placed at the feet of the exclusionary rule, rather than the Fourth Amendment) feel it is sometimes cost-justified. By contrast, there is likely no one on the current (or any past) Supreme Court who would advocate for a rule that prohibited police from saving a child after having illegally entered a home without probable cause and a warrant.

The DDE thus helps us better understand the opposing perspectives on the exclusion of evidence and the costs of that exclusion. It does not, however, dictate an answer to the bottom-line questions of (1) whether it is appropriate to have an exclusionary rule at all and (2) whether, if we do have an exclusionary rule, it should be as broad as possible or – as a majority of the current Supreme Court favors – it should be a "last resort" that we apply sparingly to only the most flagrant and deliberate abuses.

Sherry F. Colb, a FindLaw columnist, is Professor of Law and Charles Evans Hughes Scholar at Cornell Law School. Her book, When Sex Counts: Making Babies and Making Law, is available on Amazon.

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