Keeping the Republic. Christine Barbour

counsel, and to present any contradictory evidence in their defense. Due process means essentially that those accused of a crime have a right to a fair trial.

      due process of the law the guarantee that laws will be fair and reasonable and that citizens suspected of breaking the law will be treated fairly

      During the 1960s and 1970s the Supreme Court expanded the protection of the rights of the accused and incorporated them so that the states had to protect them as well. Yet the more conservative 1980s and 1990s witnessed a considerable backlash against a legal system perceived as having gone soft on crime—overly concerned with the rights of criminals at the expense of safe streets, neighborhoods, and cities, and deaf to the claims of victims of violent crimes. We want to protect the innocent, but when the seemingly guilty go free because of a technicality, the public is often incensed. The Supreme Court has had the heavy responsibility of drawing the line between the rights of defendants and the rights of society.

      Protection Against Unreasonable Searches and Seizures

      The Fourth Amendment guards against “unreasonable searches and seizures” and requires “probable cause” to obtain a warrant. The founders were particularly sensitive on this question because the king of England had had the right to order the homes of his subjects searched without cause, looking for any evidence of criminal activity. For the most part this amendment has been interpreted by the Court to mean that a person’s home is private and cannot be invaded by police without a warrant, obtainable only if they have very good reason to think that criminal evidence lies within.

      What’S Reasonable?

      Under the Fourth Amendment, there are a few exceptions to the rule that searches require warrants. Automobiles present a special case, for example, since by their nature they are likely to be gone by the time an officer appears with a warrant. Cars can be searched without warrants if the officer has probable cause to think a law has been broken, and the Court has gradually widened the scope of the search so that it can include luggage or closed containers in the car.

      Modern innovations like wiretapping and electronic surveillance presented more difficult problems for the Court because, of course, they are not mentioned in the Constitution. A “search” was understood legally to require some physical trespass, and a “seizure” involved taking some tangible object. Not until the case of Katz v. United States (1967) did the Court require for the first time that a warrant be obtained before phones could be tapped,⁷⁰ although the 2001 Patriot Act makes it a good deal easier to get a warrant. In 2012 the Court ruled that a search warrant was needed in order to put a GPS tracking device on a suspect’s car.⁷¹

      Physical searches of cell phones have also presented a modern conundrum for the courts, as cell phones have been considered to be part of the content of one’s pockets, which the Supreme Court had determined could be legally searched. But in 2014, writing for a unanimous Court, Chief Justice John Roberts acknowledged that “[t]he average smartphone user has installed 33 apps which together can form a revealing montage of the user’s life.” Thus, our phones are “mini-computers” that contain the same kind of information about us that our houses have traditionally contained, and just as our houses cannot be searched without a warrant, now neither can our cell phones (at least most of the time). It bears repeating, however, that warrants are not that hard to come by, so people storing information they prefer to keep private on their cell phones or computers should in general be cautious.⁷²

      Analog Searches Only Although police can examine personal items in certain circumstances, the Supreme Court in 2014 ruled that the digital information stored on one’s cell phone is protected by the Fourth Amendment. If the police want to look at your data, they must get a search warrant first.

      Brian Harkin/Getty Images

      Yet another modern area in which the Court has had to determine the legality of searches is mandatory random testing for drug or alcohol use, usually by urine or blood tests. These are arguably a very unreasonable kind of search, but the Court has tended to allow them where the violation of privacy is outweighed by a good purpose—for instance, discovering the cause of a train accident,⁷³ preventing drug use in schools,⁷⁴ or preserving public safety by requiring drug tests of train conductors and airline pilots.

      Finally, in 2012 the Court held, five to four, that the Fourth Amendment is not violated by the requirement that someone arrested for a minor infraction and not suspected of concealing a weapon or drugs could nonetheless be subjected to an invasive strip search. In Florence v. Board of Chosen Freeholders of County of Burlington, the majority ruled that the plaintiff could be subjected to a strip search despite the fact that he had been arrested for something that he had not in fact done and that would not have been a crime in any case. The key issue for the Court was that the defendant was going to be held in the general jail population, and correctional officers are rightly concerned with jail security, which outweighs an individual’s privacy rights.⁷⁵

      The Exclusionary Rule

      By far the most controversial part of the Fourth Amendment rulings has been the exclusionary rule. In a 1914 case, Weeks v. United States, the Court confronted the question of what to do with evidence that had been obtained illegally. It decided that such evidence should be excluded from use in the defendant’s trial.⁷⁶ This exclusionary rule, as it came to be known, meant that even though the police might have concrete evidence of criminal activity, if obtained unlawfully, the evidence could not be used to gain a conviction of the culprit.

      exclusionary rule the rule created by the Supreme Court that evidence seized illegally may not be used to obtain a conviction

      The exclusionary rule has been controversial from the start. In some countries, including England, illegally obtained evidence can be used at trial, but the defendant is allowed to sue the police in a civil suit or to bring criminal charges against them. The object is clearly to deter misbehavior on the part of the police, while not allowing guilty people to go free. But the exclusionary rule, while it does serve as a deterrent to police, helps criminals avoid punishment. The Court itself has occasionally seemed uneasy about the rule.⁷⁷ Not until the 1961 case of Mapp v. Ohio was the exclusionary rule finally incorporated into state as well as federal practice.⁷⁸ But extending the reach of the exclusionary rule did not end the controversy. Although the Warren Court continued to uphold it, the Burger and Rehnquist Courts cut back on the protections it offered. In 1974 they ruled that the exclusionary rule was to be a deterrent to abuse by the police, not a constitutional right of the accused.⁷⁹ The Court subsequently ruled that illegally seized evidence could be used in civil trials⁸⁰ and came to carve out what it called a good faith exception, whereby evidence is admitted to a criminal trial, even if obtained illegally, if the police are relying on a warrant that appears to be valid at the time or on a law that appears to be constitutional (though either may turn out to be defective),⁸¹ or on a warrant that is obtained in error. In 2009 the Roberts Court ruled that to trigger the exclusionary rule, the police conduct must be deliberate.⁸² The Court’s more conservative turn on this issue has not silenced