Due Process & Rights of the Accused

Our life, liberty, and property is protected under the Constitution and cannot be taken from us without due process of law. The protection of those rights are not absolute, meaning there are times when our life, our freedom, and/or our property can be taken away from us–just like the other rights we’ve studied in this unit. Due process of law refers to the fair and impartial application of our laws any time the government seeks to infringe upon life, liberty, or property.

What you need to learn

Skill to Practice:

Fourth Amendment

-Exclusionary Rule

-Weeks v. United States

-Mapp v. Ohio

-Digital data & the Patriot Act

-Riley v. California

Sixth Amendment

-Gideon v. Wainwright

Fifth Amendment

-Miranda v. Arizona & the Miranda Rule/Rights

-public safety exception


U.S. Constitution, 4th, 5th, 6th, & 14th Amendments

Due Process Case Summaries

So many of the rights that protect us today come from court cases where a defendant was charged and convicted of a crime, and appealed their conviction because they believed their constitutional rights had been violated. These landmark cases change the way law enforcement conduct investigations, and what is admissible at trial.

Weeks v. United States, 232 U.S. 383 (1914)


In Kansas City, Missouri, Fremont Weeks was suspected of transporting lottery tickets through the mail, which was a federal offense. Without a search warrant, federal agents entered and searched Weeks’ home during his absence, and seized various papers and materials. Weeks was subsequently arrested at his place of employment, and again, the agents conducted a search and seized letters and envelopes from him. After being taken to the federal building, a third warrantless search was conducted of his belongings.

The seized items were used as evidence during Weeks’ trial in a federal district court, and he was found guilty. Weeks filed a motion with the trial court to return his private possessions, arguing that they had been illegally seized. The motion was denied, leading Weeks to appeal to the U.S. Supreme Court.


The main issue was whether evidence obtained from a private residence through a warrantless search and seizure, which violates the Fourth Amendment, could be used in federal courts.


The U.S. Supreme Court reversed the decision of the lower court, ruling in favor of Weeks. The Court held that the warrantless seizure of items from a private residence constitutes a violation of the Fourth Amendment, and that such illegally obtained evidence is inadmissible in federal court.


The Supreme Court, in its opinion delivered by Justice Day, reasoned that the Fourth Amendment, which protects citizens from unreasonable searches and seizures, should be upheld in federal cases. The exclusionary rule was created in this case, establishing the principle that evidence obtained in violation of the Fourth Amendment could not be used in federal courts.

The Court underscored the importance of the Fourth Amendment as a protection of individual rights. The majority noted that, if federal authorities can break into a home, seize items without a warrant, and then use those items as evidence in court, the Fourth Amendment would be of no value.


The ruling in Weeks v. United States established the exclusionary rule in federal court, setting a precedent for the protection of individual rights against unwarranted government intrusion. However, it would take several more decades, until the case of Mapp v. Ohio in 1961, for this rule to be applied to state courts via the Due Process Clause of the Fourteenth Amendment.

Mapp v. Ohio, 367 U.S. 643 (1961)


In 1957, Cleveland police officers suspected Dollree Mapp of harboring a bombing suspect and possibly being in possession of illegal betting equipment. They went to her home and demanded entry. Mapp refused to let them in without a search warrant. A few hours later, the police returned, forcibly entered her residence, and conducted a search. They did not find the bombing suspect but discovered allegedly obscene materials. Mapp was arrested and later convicted under Ohio law for possession of these obscene materials.

Mapp appealed her conviction, arguing that the obscene materials were obtained during an illegal search of her home. At her trial, the prosecution did not produce any search warrant. Mapp’s attorney argued that the materials should be excluded from evidence, but this argument was rejected, and she was found guilty.


The key question before the U.S. Supreme Court was whether the Fourth Amendment’s protection against unreasonable searches and seizures, which excludes unlawfully seized evidence from federal courts (as established in “Weeks v. United States”), also applied to state courts through the Fourteenth Amendment’s Due Process Clause.


The U.S. Supreme Court ruled in favor of Mapp, overturning her conviction. The Court held that the evidence obtained during the illegal search was inadmissible in state court. The decision effectively extended the Fourth Amendment’s “exclusionary rule” to states.


Justice Tom C. Clark delivered the majority opinion. The Court emphasized the importance of the Fourth Amendment’s protections and how they serve as a vital component of the Fourteenth Amendment’s guarantee of due process. The majority believed that without the exclusionary rule, the Fourth Amendment would be a mere “form of words.”

Furthermore, the Court felt that the only effective way to deter law enforcement from unconstitutional searches and seizures was to exclude evidence obtained in such a manner. Thus, the exclusionary rule was deemed necessary not just for federal courts, but for state courts as well, to ensure the protection of constitutional rights.


The decision in Mapp v. Ohio was a landmark ruling in criminal procedure. By incorporating the exclusionary rule against the states, the ruling provided a critical tool for defendants in both state and federal courts to challenge evidence obtained in violation of their Fourth Amendment rights. This expanded protection has had a lasting impact on the conduct of law enforcement across the country, emphasizing the importance of constitutional rights and due process at all levels of the American judicial system.

Miranda v. Arizona, 384 U.S. 436 (1966)


In 1963, Ernesto Miranda was arrested in Phoenix, Arizona, based on circumstantial evidence linking him to the kidnapping and rape of an 18-year-old woman. After two hours of interrogation by police officers, Miranda signed a confession to the crimes. The confession was written on a form that stated he was fully aware of his legal rights, understood the statement was made voluntarily, and was made without threats or promises of immunity. However, at no point during the interrogation was Miranda informed of his right to counsel or his right to remain silent.

Miranda’s confession was later used as evidence at his trial, and he was found guilty of both rape and kidnapping. He was sentenced to 20 to 30 years in prison on each charge. On appeal, Miranda’s attorney argued that his confession was not truly voluntary because he had not been informed of his rights.


The primary issue before the U.S. Supreme Court was whether statements obtained from an individual while in police custody, without being informed of their Fifth Amendment rights against self-incrimination and to counsel, can be admissible in court.


The U.S. Supreme Court ruled in favor of Miranda, holding that prosecutors cannot use statements resulting from custodial interrogation of a suspect unless they demonstrate the use of procedural safeguards to secure the suspect’s Fifth Amendment rights. Before an interrogation begins, the police must inform the suspect of their specific rights.


Chief Justice Earl Warren delivered the opinion of the Court. He outlined the necessary safeguards, which have since become known as the “Miranda rights.” These include the right to remain silent, the warning that anything the suspect says can and will be used against them in a court of law, the right to have an attorney present, and the right to have a court-appointed attorney if the suspect cannot afford one.

The Court emphasized the inherently coercive nature of custodial interrogation and the need for specific warnings to ensure that a suspect is aware of their rights. It also noted the fundamental role of the Fifth Amendment in ensuring that individuals are not compelled to incriminate themselves.


The decision in Miranda v. Arizona significantly impacted law enforcement procedures in the U.S. It established the principle that unless individuals in police custody are informed of their rights, their statements may be considered involuntary and cannot be admitted as evidence in court.

The term “Miranda rights” or “Miranda warning” became part of the national lexicon, encapsulating the specific rights that law enforcement officials are now required to communicate to individuals upon arrest. This decision aimed to protect individuals’ constitutional rights and ensure fair treatment during interactions with the criminal justice system.

Riley v. California, 573 U.S. 373 (2014)


David Riley, a member of a gang in San Diego, California, was pulled over by the police for having expired registration tags on his vehicle. After discovering that Riley was also driving with a suspended license, the police impounded his car. In a subsequent inventory search of the car, officers found loaded firearms. Riley was arrested on weapons charges.

Following his arrest, the police took possession of Riley’s smartphone and proceeded to access its contents without a warrant. Through this search, they found evidence suggestive of gang affiliation, including videos, photos, and contacts. This digital evidence was then used to charge Riley with shooting at an occupied vehicle, attempted murder, and assault with a semi-automatic firearm. The evidence from the phone played a significant role in his conviction, leading to a sentence of 15 years to life in prison.

Riley appealed, claiming that the warrantless search of his smartphone violated his Fourth Amendment rights against unreasonable searches and seizures.


The primary issue the Supreme Court considered was whether the police can, without a warrant, search the digital contents of a cell phone seized from an individual who has been arrested.


The U.S. Supreme Court ruled unanimously in favor of Riley, holding that the warrantless search of his smartphone’s digital contents during his arrest violated the Fourth Amendment. The police generally need a warrant before searching a smartphone seized incident to an arrest.


Chief Justice John Roberts delivered the opinion of the Court. In the decision, the Court acknowledged that while searching an arrestee without a warrant is allowable under certain conditions (such as ensuring officer safety or preventing evidence destruction), smartphones are distinct from other physical items because of the vast amount of personal and private information they contain.

The Court noted that digital data stored on cell phones cannot be used as a weapon to harm officers or facilitate an escape. Additionally, the risks of evidence destruction on phones (like remote wiping or encryption) could be mitigated by other means that do not involve a thorough search, such as using “Faraday bags” to block signals.

The Court emphasized that modern smartphones are not just phones but mini-computers that contain a vast array of personal information, from photographs and emails to banking data and location information. Because of the immense privacy concerns, the Court concluded that the rationale for the search incident to arrest exception did not apply in the context of smartphones.


Riley v. California marked a significant decision in Fourth Amendment jurisprudence in the context of evolving technology. The ruling recognized the distinct nature of smartphones and the expansive personal data they contain, offering robust privacy protections for individuals in the digital age. The decision was hailed by privacy advocates for striking a balance between law enforcement needs and individual privacy rights in the modern era.