In the United States, one of the ways that the judicial branch checks the executive branch is via the exclusionary rule. Under this law, illegally obtained evidence has been inadmissible in federal criminal courts since 1914. Proponents of this rule find that it helps eliminate police misconduct and protect individual rights, while opponents believe that society is punished and criminals benefit from errors made by the police.

In the 1961 case of Mapp v. Ohio, the exclusionary rule was extended to the states. At that time, televisions had just recently become a standard in the American household and the average American had no concept of what a computer might be. However, by the 1990s, computers were as much a part of American's lives as televisions. Increasing technological skills allowed computers to be used by law enforcement officers as a standard part of their job.

As technology was evolving, so were the Court's standards regarding the controversial exclusionary rule. In a series of cases, the Court recognized several exceptions. For instance, in the 1984 case United States v. Leon, the Court relaxed the standard a bit to include "good faith" exceptions. The Court held that if police believed, for instance, that a search warrant was legal, but later found out that it was technically flawed, the evidence obtained in the search would still be admissible, so long as the police had acted in "good faith."

Question: Does the exclusionary rule apply to computer errors made by the police?

The Case: Arizona v. Evans

The police stopped Evans for driving the wrong way down a one-way street. After running his driver's license through their computer, the police found that there was a warrant out for his arrest connected to a misdemeanor. Arresting Evans, the police searched his car and found marijuana.

A search "incident to arrest" (connected to a lawful arrest) is generally understood to be constitutional. However, it turned out that the misdemeanor warrant that appeared on the police officer's computer was a mistake. The warrant had been withdrawn. At his trial, Evans argued that the computer mistake meant the search of his car was illegal. Because his car was illegally searched, he stated, the exclusionary rule should apply to the marijuana the police found.

The Supreme Court of Arizona basically agreed with Evans that the search and resulting drug charges were unconstitutional. They ruled that because the exclusionary rule is meant to deter police employees from making mistakes in the process of searching for and seizing evidence, computer records were not exempt from the rule.

In 1994, the Supreme Court of the United States decided to hear the case upon appeal from the Arizona police.

Questions to Consider

  1. What is the purpose of the exclusionary rule? 

  2. Should it apply in this case? Why or why not? 

  3. Predict the outcome of the case.

When your teacher gives you the next handout, review the main arguments made in the case and then decide which ones are most compelling.

Then, your teacher will divide the class into groups of three. Each triad will contain a lawyer for Evans, a lawyer for Arizona, and a justice. The lawyers will present their most persuasive arguments and the justice will make a ruling and explain which arguments were the most persuasive.

After you complete this exercise, your teacher will distribute the Supreme Court's decision in this case.

Note to Teachers:

The handouts mentioned in this activity are all available in the downloadable document linked in the "Answers & Differentiation Ideas" tab.