Criminals May Go Free When Constable Blunders

​​​​The Fourth Amendment spells out an important right to be free of unlawful intrusion by the police and other government agencies. But the brief amendment does not say what happens when it is violated.

In 1961, when the United States Supreme Court decided Mapp v. Ohio, the consequence of violating this amendment was clarified, and since then, no evidence obtained as a result of an unlawful search and seizure can be used in a criminal prosecution. This is known as the exclusionary rule, and it was summarized by Judge, later Justice, Benjamin Cardozo: “The criminal is to go free because the constable has blundered.”

Q: Does this mean an entire case must be thrown out because one bit of evidence was collected illegally?
No. Even if some unlawfully uncovered evidence is excluded, the defendant may still be convicted based on other evidence. And there are exceptions to the rule. For example, when unlawfully seized evidence would have been obtained anyway, that evidence may be used. Nevertheless, in some cases, a guilty defendant will go free. For example, a drug user will go free when the drugs found on his person (the only evidence against him) were found as the result of an unlawful search.

Q: Why did the U.S. Supreme Court make the “exclusionary rule” decision in 1961?
To see the rationale for this rule, we can look at the situation before 1961. Earlier, the Supreme Court recognized that the Fourth Amendment did apply to states, but allowed each state to impose its own consequences for violations, through “private action” or through internal police discipline.

Consider the shortcomings of “private action” (lawsuits) against the police. On one hand, if the unlawfully searched individual were innocent, how often would he or she want to sue the police and thereby publicize that he was the subject of suspicion? On the other hand, if the unlawful search turned up incriminating evidence against a disreputable individual, how likely is it that a jury would award him or her substantial damages for the unlawful search? How many attorneys are likely to want to take such a case? In a nutshell: innocent individuals are unlikely to sue, and disreputable ones may sue but are unlikely to win. Consequently, the prospect of such lawsuits will not do much to deter unlawful searches.

Then consider another possible remedy, the internal discipline of the police. Fellow police officers are only too aware that it is both important and difficult to obtain evidence, and they are often frustrated by the fact that they “know” someone is guilty, but cannot get the evidence necessary for a conviction. How effective is the police department likely to be in disciplining officers who break the rules to get evidence that might be used to take a “known” criminal out of circulation?

In contrast, with the exclusionary rule, police officers know that unlawfully obtained evidence will be useless, and that, if they break the rules, they may contribute to letting a criminal go free. As a result, they have a strong incentive to search for evidence within the limits of the law.

Q: Are there any other rules similar to the exclusionary rule?
A: Yes. One is Ohio’s statutory speedy trial rule. Under it, the state has a certain amount of time, depending upon the seriousness of the charge, to bring a criminal defendant to trial. If the rule is violated, the defendant is entitled to be discharged. It doesn’t matter if the proof of the defendant’s guilt is clear; if the defendant isn’t brought to trial within time, he or she walks.

This rule is rarely applied, however, because criminal defendants are almost always brought to trial within time, unless they themselves waive their speedy trial rights.

The exclusionary rule and Ohio’s speedy trial rule can be called “prophylactic” rules: because they impose harsh and certain consequences on violations, the police and other government agencies work hard to stay within the rules.


This "Law You Can Use" consumer legal information column was provided by the Ohio State Bar Association. It​ was prepared by Judge Mike Fain of the 2nd District Court of Appeals in Dayton.

Articles appearing in this column are intended to provide broad, general information about the law. This article is not intended to be legal advice. Before applying this information to a specific legal problem, readers are urged to seek advice from a licensed attorney.



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