42 Section 4.5: The Legal Environment of Policing

Criminal law is often used as a very general term to describe the entire body of law that is of concern to the criminal justice system. Recall that the two major parts are the substantive criminal law and the procedural criminal law. The substantive criminal law consists largely of statutes that define criminal acts. The procedural criminal law dictates how the criminal justice system should treat people. Because the police are the gatekeepers of the criminal justice system and come into contact with citizens far more often than any other component of the criminal justice system, the law of criminal procedure has more to say about how the police treat people than any other topic.

Criminal procedure, then, can be seen as a branch of law that dictates how the government investigates, prosecutes, judges, and sentences those accused of crimes. The bulk of this law is a matter of interpreting the Constitution of the United States. When it comes to how the police must treat people, the most important body of law stems from the Bill of Rights. The Supreme Court of the United States interprets the Bill of Rights, and that court has the power to establish police practice in the field. There are also state constitutions, statutes, and administrative rules that circumscribe police conduct. These are also part of the body of procedural law. Perhaps the most important laws that concern police conduct are the Fourth and Fifth Amendments of the United States Constitution.

The Fourth Amendment States that: “The right of the people to be secure in their persons, houses, papers and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”

The Fifth Amendment states that: “No person … shall be compelled in any criminal case to be a witness against himself, nor be deprived of life, liberty, or property, without due process of law.”

The Sixth Amendment guarantees the right to a public and speedy trial, as well as the right to the assistance of counsel. The right to counsel is protected at many stages of the criminal justice process, not just at trial. Criminal defendants have the right to an attorney during custodial interrogations, for example.

The Fourteenth Amendment requires the States to observe the due process standards set forth in the federal Constitution as interpreted by federal appeals courts. This gives the federal appellate courts the authority to consider the constitutionality of acts of government agents employed by the state such as police officers and corrections officers. It also gives the high courts the authority to review the constitutionality of state statutory laws. Not all federal constitutional rights are considered to be due process rights, so some protections are not forced on the states. For example, many states do not observe the right to an indictment by a grand jury; they use a system of prosecutorial information instead.

  The Right to Privacy

To understand how the Constitution of the United States limits the criminal law, it is important to consider the right to privacy. Shockingly, the term “privacy” never appears in the Constitution. Yet, over the years, the Supreme Court has said that several of the rights that are explicitly stated in the constitution come together to create a right to privacy. In the world of procedural law, it must be remembered, if the Supreme Court of the United States says it, it is so.

The right to privacy places a limit on many forms of police conduct, from searches to arrest. It is important, however, to understand there is a limit to how far the right goes. It is not absolute. The police are not prohibited from interfering with a citizen’s privacy interest, but it must be reasonable when they do so.

When it comes to the police conducting searches of people, vehicles, homes, offices and anywhere else a person has a right to privacy, the idea of reasonableness comes down to probable cause. Probable cause means that there is sufficient evidence to make a reasonable person would believe that the person is doing something contrary to the law.


Police activity that the courts consider a search must be based on probable cause, but remember that the courts define a search differently that the everyday use of the term. There are many exceptions to the probable cause requirement that, while the average person may consider the police conduct a search, it is not considered so by the courts. Objects in plain view, for example, are not subject to the probable cause standard, nor are things located in open fields. When the probable cause standard does apply because the courts consider a particular police action a search, the police are not allowed to determine if there is in fact probable cause. That job goes to the courts.

Search warrants

An officer desiring to conduct a search needs probable cause for the search to be lawful. Because society expects police officers to find evidence and arrest criminals, they may be overzealous in determining whether the do or do not have probable cause. As a general rule, the evidence establishing probable cause must be submitted to an impartial magistrate, and if the magistrate agrees that probable cause exists, then he or she will issue a search warrant.

Probable Cause

For a warrant to be issued, the magistrate must determine that probable cause exists. This has to be in the form of a sworn statement called an affidavit. When determining probable cause for a search, the reasonableness test used by the courts considers the experience and training of police officers. That is, the test is not merely what a reasonable person would believe, but what a reasonable police officer would believe in light of the evidence as well as the officer’s training and experience. Note that the standard for establishing probable cause is more likely than not. This is a far lesser standard that the proof beyond a reasonable doubt standard required for a conviction in criminal court.

The Particularity Requirement

Another requirement for a search warrant to be valid is that it must particularly describe the person or thing to be seized. There are many supreme court cases that establish what this means in particular circumstances. As a general rule regarding search warrants, it means that the place to be searched is sufficiently described that it cannot be confused with some other place.

Obtaining and Executing a Search Warrant

The warrant application process varies in exact detail from jurisdiction to jurisdiction. Often, the Supreme Court of the state in which the warrant is sought provides the details in a legal document known as the Rules of Criminal Procedure. The basic rules, however, are dictated by the Supreme Court as interpretations of the Fourth Amendment. All of the officer’s evidence must be contained in an affidavit. The rules also dictated how a warrant must be executed. As a general rule, the warrant must be served during daylight hours, and officers must identify themselves as officers and request entry into the place to be searched. This identification requirement is known as knock and announce.

No-knock Warrants

The general rule that officers must “knock and announce” when serving a warrant is not absolute, but special permission from a judge must be obtained before it can be lawfully circumnavigated. A no-knock warrant can be issued have a legitimate fear that announcing their presence would endanger lives or give criminals time to destroy evidence. Such a warrant authorizes law enforcement to break down doors without warning and to enter a structure. These types of warrants are controversial. Civil liberty advocates say that such warrants violate the spirit of the Fourth Amendment. Police defend such warrants on the grounds that they save lives and very frequently result in the seizure of contraband.

  Searches Without Warrants

There are several exceptions to the general requirement that officers must obtain search warrant for a search to be legal. The Supreme Court has determined that exigent circumstances justify an exception to the rule. Exigency is another word for emergency. Thus an exigent circumstances search is an entry into a place that would otherwise require an warrant but for the emergency situation.

Another common warrantless search is a consent search. Most of the rights guaranteed by the constitution can be waived by the person that has the right. If a person gives the police permission to search, so long as the permission is given voluntarily, then there is no violation of the person’s Fourth Amendment rights. A shocking amount of criminal convictions come as a result of consent searches. Many criminals do not do what is in their legal best interest. According to the Supreme Court of the United States, the police are not obligated to inform citizens that they have the right to refuse consent. Some state courts (e.g. Arkansas), however, have interpreted state constitutions to give this right.

Another exception to the general requirement that police have a warrant to conduct a search is known as a hot pursuit search. If an officer chases an offender into a private place, there is no legal requirement that the officer break off the pursuit. If contraband is discovered in such a pursuit, it can be seized and will be admissible in court.

Most of the exceptions to the warrant requirement above do not, for one reason or another, require probable cause. An automobile search is an interesting hybrid because it does require probable cause to obtain a warrant, even though the officer is not obligated to actually obtain the warrant. The court allows this compromise because of the inherent mobility of vehicles. The criminal suspect could simply drive away of the officer were required to leave the scene and go obtain a warrant. Merely citing the driver for a traffic violation, however, is not sufficient to establish probable cause for a lawful search.

To preserve evidence and to protect officers from hidden weapons, officers are allowed to search a person after they have been arrested. Such a search is known as a search incident to arrest. As an extension of this idea, the officer may search the area immediately surrounding the arrested person. That is, the area immediately under the arrestee’s control. The Court has ruled the fact that the suspect is in handcuffs and could not reach for a weapon is immaterial.


The Supreme Court has determined that an arrest is a seizure of the person for legal purposes. Accordingly, the Fourth Amendment prohibition against unreasonable searches and seizures comes into play. A person is generally considered to have been arrested when they are taken into custody with the purpose of being charged with a crime.

Most arrests are made without arrest warrants, despite the constitution’s general requirement that officers have one. Under all circumstances, an officer must have probable cause to make an arrest. When it comes to arrests, probable cause means that the officer has reasonable grounds to believe that the person has committed or is about to commit a crime. When a warrant is sought, the supporting evidence must be included in an affidavit, just as with a search warrant.

The old common law rule was that an officer could make an arrest, without a warrant, if he believed he had evidence amounting probable cause that the person had committed a felony. In the case of a misdemeanor, the crime had to be committed in the officer’s presence. These same basic common law rules are still followed in many jurisdictions today. Many jurisdictions, however, have created special rules where misdemeanors that the officer did not witness directly (such as with many domestic battery statutes) can result in lawful arrests without a warrant. Such rules are usually created by state legislatures as a matter of statute.

  Arrest Warrants

As previously described, an arrest warrant is a document issued by a court ordering any law enforcement officer to take a particular individual into custody. While there are many exceptions, there are times when a warrant is required to make a lawful arrest. To enter a person’s home to make an arrest, the police must have an arrest warrant. (To enter the home of someone other than the person to be arrested to make an arrest, the police must have a search warrant). Of course, the exigent circumstances exception can be applied to arrest warrants just as it can with search warrants.

  Domestic Violence Arrests

Social scientific research as resulted in at least some evidence that arresting the primary aggressor in domestic violence cases prevents further battering. This research spawned legislation in many states that require police to identify and arrest the primary aggressor in domestic violence situations. While these offenses are generally classified as misdemeanors, these special legislative enactments command law enforcement to take the primary aggressor into custody despite not having a warrant or having seen the crime take place. Despite such laws being in place in many jurisdictions since the 1970s, many police departments do a poor job in dealing with domestic violence cases.

  Terry Stops

Making an arrest is a substantial interference with a citizen’s constitutionally protected freedom. As such, it requires probable cause. The courts have ruled that there are sorts of intrusions that are less than an arrest, and thus require a lesser standard of evidence. Because the Supreme Court described this sort of situation in a 1968 case styled Terry v. Ohio, these types of “stops” are often referred to as Terry stops. In Terry, the court said that the police have the right to stop individuals for a short period of time when their behavior seems suspicious, ask them questions, and pat them down for weapons. This type of stop is also known as a stop and frisk. The evidentiary standard set forth in Terry was less than probable cause, but more than a mere hunch. The court called this standard reasonable suspicion. Unlike courtroom testimony, reasonable suspicion can be based on hearsay.

  The Exclusionary Rule

As previously discussed, the Supreme Court of the United States can tell law enforcement officers how to treat people as long as they have a constitutional reason for doing so. What happens if the cops do not listen to the Court and violate somebody’s rights? There are several remedies, but the most important one to the criminal justice system is the exclusionary rule. The exclusionary rule is very simple. It states that illegally obtained evidence cannot be admitted into a criminal court. Here, illegally obtained means obtained in violation of the defendant’s constitutional rights. In practice, the defendant’s attorney must file a motion to suppress the evidence before trial. The judge will then review the evidence, and if the judge determines that it was obtained in violation of the defendant’s rights, it will be suppressed, and the jury will never see the evidence. Its existence cannot even be mentioned at trial.

The exclusionary rule was established by the U.S. Supreme Court in 1914 in the case of Weeks v. U.S. At that time, the rule only applied to Federal agents. States were on their own to decide whether to allow illegally obtained evidence into state courts. It was not until 1961 in Mapp v. Ohio that the Court decided that the exclusionary rule was fundamental to a fair trial and was thus applicable to the state via the Fourteenth Amendment’s due process clause. The liberal Warren Court decided Mapp. Since the time of the warren court, the Supreme Court has become more and more conservative. Conservative justices, while not willing to overrule the basic premise of the exclusionary rule, have eroded it by creating various exceptions. For example, in the 1984 case of U.S. v. Leon, the court created a good faith exception. The good faith exception states that if the police are acting on a warrant they believe to be valid and a court later determines that the warrant is invalid, the evidence can still be used in court.

  The Fifth Amendment

The common expression “to plead the fifth” refers to the Fifth Amendment to the United States Constitution. The Fifth Amendment gives criminal defendants the right to remain silent, and thus is a right against self-incrimination. The Fifth Amendment has an enormous impact on the practice of police interrogations.

In the days before the civil rights revolution, the police would use any means necessary to gain a confession. Torture, both physical and psychological, was shockingly common. Threats were often used. The problem with confessions made under such duress is that innocent persons may well confess to crimes simply to make the pain stop. The first major case prohibiting this sort of conduct was Brown v. Mississippi (1936).

The right against self-incrimination is not as broad as it may first seem. It applies only to confessions. That is, communications that are considered “testimonial” in court. The protection does not extend to physical evidence, so a suspect can be compelled to give fingerprints, DNA samples, blood tests, blood alcohol tests, and so forth. Just as with most constitutional rights, a person can knowingly and voluntarily waive the right to remain silent. If it were not for such waivers, the art of interrogation would hold little value for police.

Confessions and Counsel

The Court has linked the Fifth Amendment right against self-incrimination to the right to counsel. In the case of Escobedo v. Illinois (1964), the Court ruled that when police questioning moves from merely investigatory to accusatory in nature, the right to counsel becomes active. In other words, once a witness develops into a suspect, then the right to comes into play.

Miranda Warnings

Ultimately, the court was not satisfied with the scope of the protections set forth in Escobedo. Two years later, the court established specific interrogation procedures to ensure the Fifth Amendment rights of criminal defendants in Miranda v. Arizona (1966). In this landmark case, a man named Miranda confessed to kidnapping and rape. Police obtained the confession without a lawyer being present and without advising Miranda that he had the right to remain silent. The Court held that Miranda was entitled to such a warning, and thus his confession was inadmissible.

The decision in Miranda reached far beyond Miranda’s case. It obliged every police officer in America to advise suspects if their rights before asking them questions while in custody. In addition to being advised of the right to remain silent, suspects must be advised that anything that they do say can be used against them in court, that they have the right to an attorney, and that if they cannot afford an attorney they will be provided one by the state. Of course, the suspect may knowingly and voluntarily waive any or all of these rights. The right to remain silent can be invoked at any time. In other words, even if suspects waive their right to remain silent, they can stop the questioning at any time, and must be provided with a lawyer if they so request.

Many police officers and conservative commentators at the time regarded Miranda as a legal technicality created by the courts to handcuff the police. On several occasions, increasingly conservative courts have refused to overrule Miranda, but they have weakened it by creating several exceptions to it. For example, in New York v. Quarles (1984), the Court created a public safety exception. The public safety exception allows officers to ask questions without giving the Miranda warnings if there is some exigency involving the public safety is involved. In Nix v. Williams (1984), the court created the inevitable discover exception. This controversial exception means that if the police would have inevitably discovered the evidence without benefit of the improper questioning, then the evidence will be admissible.

There are many situations in which the person may not necessarily feel free to leave, but they are not in “custody” for Miranda purposes. For example, Miranda does not come into play when the police stop a person to (briefly) talk to them on the street, or during traffic stops. Other circumstances do not invoke Miranda because there is no questioning of the suspect involved. For example, if a person confesses to an officer without the officer asking any questions, then Miranda does not apply.

  Police Use of Force

Police officers have the lawful authority to use force, but only if that force is reasonably necessary to accomplish a legitimate criminal justice purpose. Obviously, taking a person into custody by making an arrest, or preventing a suspect from fleeing are examples of legitimate criminal justice purposes. Most questions about the legitimacy of police use of force revolve around the reasonableness of it. If too much force is used, then the use of force will not be lawful. The problem is that defining how much force is necessary in a given situation is a highly subjective process. When the police use more force than someone regards as reasonable in a given situation, it is often referred to as police brutality.

  Civil Liability and Criminal Prosecution

When the police go beyond reasonable, legitimate use of force, they risk law suits and criminal charges. Under the laws of most states, individual police officers can be sued for torts, such as wrongful death and false imprisonment. There are also federal remedies in place, such as 1983 suits.

Deadly Force

As one would expect, police officers have the legal right to use deadly force (most often a shooting) when they reasonably believe that they are in imminent danger of serious bodily harm or death. That right extends to the protection of others. Until the court’s decision in Tennessee v. Garner (1985), many jurisdictions subscribed to the idea of the fleeing felon rule. The fleeing felon rule was the common law doctrine that allowed an officer to use deadly force to apprehend a felon that was seeking to escape custody or a lawful arrest. In Tennessee v. Garner, the court struck down a Tennessee statute stating “if, after notice of the intention to arrest the defendant, he either flee or forcibly resist, the officer may use all the necessary means to effect the arrest.” This, in effect, declared the fleeing felon rule unconstitutional. With the abolishment of the fleeing felon rule, the standard become one of dangerousness.

Law Enforcement Jobs Outlook

According to the Bureau of Labor Statistics (2013), the median income for police officers and detectives in 2010 (the most recent statistics available) was $55,010 per year (or $26.45 per hour). There were 794,300 such jobs in the United States, and the expected growth rate over the next decade is projected to be around 7%. Of course, this does not reflect the fact that local political and economic conditions are a major factor in any particular agency’s decision to hire new officers. The prediction is that local agencies will do most of the new hiring, and that federal jobs will remain very competitive. According to the BJS, average starting salaries for entry-level local police officers in 2007 ranged from $26,600 per year in the smallest jurisdictions to $49,500 in the largest. Overall, the average starting salary earned by entry-level officers was about $40,500. More than 90% of local police departments serving 25,000 or more residents were using in-field computers during 2007. This suggests that those looking to careers in law enforcement should develop computer skills.

Key Terms

1983 Suit, Affidavit, Arrest Warrant, Automobile Search, Brown v. Mississippi (1936), Consent Search, Escobedo v. Illinois (1964), Exigent Circumstances Exception, Fleeing Felon Rule, Hot Pursuit Search, Inevitable Discovery Exception, Knock and Announce, Mere Hunch, New York v. Quarles (1984), Nix v. Williams (1984), No-knock Warrant, Open Fields Doctrine, Particularity Requirement, Plain View Doctrine, Police Brutality, Primary Aggressor, Public Safety Exception, Reasonable Person Test, Reasonable Suspicion, Remedy, Right to Remain Silent, Rules of Criminal Procedure, Sixth Amendment, Stop and Frisk, Tennessee v. Garner (1985), Terry Stop, U.S. v. Leon (1984), Weeks v. U.S. (1914)


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