Arrests in Criminal Cases

Arrests in Criminal Cases

An arrest is one of the most significant exercises of government power in a criminal case. Unlike a brief investigative detention, an arrest places a person under a substantially greater restraint of liberty and ordinarily marks the transition from preliminary investigation to formal custodial control.

In U.S. criminal procedure, an arrest generally occurs when law enforcement uses legal authority to take a person into custody or otherwise restrains the person’s freedom of movement to the degree associated with formal custody. The constitutional basis for arrests is principally the Fourth Amendment, which protects individuals against unreasonable seizures and requires probable cause for warrants.

An arrest is therefore not simply a more serious police stop. It is a distinct legal event that triggers additional constitutional, statutory, and procedural protections.

The Cornell Law School Legal Information Institute’s Wex explanation of arrest describes an arrest as the use of legal authority to deprive a person of freedom of movement. An arrest generally requires probable cause, although the precise rules governing warrants, warrantless arrests, and the place of arrest depend on the circumstances and applicable law.

Understanding arrests requires distinguishing several related concepts: probable cause, arrest warrants, warrantless arrests, investigative detention, custodial interrogation, and judicial review after arrest.

What Is an Arrest?

An arrest is a governmental seizure of a person for the purpose of taking that person into custody in connection with suspected criminal activity.

The essential characteristic is a substantial restraint on liberty.

An officer does not necessarily have to use the word “arrest.”

Likewise, a person does not necessarily have to be handcuffed for an arrest to occur.

Courts examine the actual circumstances, including the degree of restraint, the officer’s conduct, the purpose of the detention, and whether the person was effectively placed under police custody.

For example, an officer who briefly stops a person on the street to investigate a suspected robbery is ordinarily conducting an investigative detention.

If the officer develops probable cause and takes the person into custody for the suspected offense, the encounter may become an arrest.

The distinction matters because reasonable suspicion may justify the first action, while probable cause is generally required for the second.

The Constitutional Foundation

The Fourth Amendment provides the principal constitutional framework for arrests.

It protects “[t]he right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures” and provides that warrants may issue only upon probable cause supported by oath or affirmation and particularity.

An arrest is a seizure of the person.

The constitutional question is therefore whether the seizure was reasonable and whether the government possessed the necessary legal justification.

The Fourth Amendment does not require that every arrest be preceded by a warrant. The constitutional requirements differ depending on the circumstances, including where the arrest occurs and whether police have time and legal authority to obtain a warrant.

Probable Cause for an Arrest

The central constitutional requirement for an arrest is generally probable cause.

Probable cause exists when the facts and circumstances known to the officer at the relevant time would lead a reasonable person to believe that the person being arrested committed or is committing a crime.

The Cornell Wex discussion of probable cause explains that probable cause is generally required before police may make an arrest and that the determination is based on the totality of the circumstances known to law enforcement.

Probable cause is higher than reasonable suspicion but lower than the proof required for a criminal conviction.

This creates an important progression:

Reasonable suspicion → investigative detention

Probable cause → arrest

Proof beyond a reasonable doubt → criminal conviction

These standards perform different functions at different stages of a criminal case.

An Arrest Is Not a Finding of Guilt

An arrest does not mean that the person has been proven guilty.

This distinction is fundamental.

Police may have probable cause to believe that a person committed a crime even though the evidence ultimately proves insufficient for conviction.

For example, a person may be arrested for burglary because the circumstances provide probable cause. The prosecution may later dismiss the charge, or a jury may acquit the defendant because the government cannot establish guilt beyond a reasonable doubt.

The arrest and the conviction involve different legal standards.

An arrest is a determination that sufficient grounds exist for taking the person into custody.

A conviction requires proof of criminal guilt at trial under the applicable burden of proof.

Arrest Warrants

An arrest warrant is a judicial order authorizing law enforcement to take a specified person into custody.

An arrest warrant is generally issued by a judge or magistrate after the government presents sufficient information to establish probable cause.

Cornell’s Wex materials describe an arrest warrant as a document issued by a judge or magistrate authorizing police to take an accused person into custody upon a sufficient showing of probable cause.

The warrant serves several functions.

It provides judicial authorization for the arrest and places a neutral judicial officer between the investigative authorities and the exercise of arrest power.

The warrant ordinarily identifies the person to be arrested and the criminal basis for the arrest.

What Must Support an Arrest Warrant?

An arrest warrant generally requires a showing of probable cause.

The government may present information through a complaint, affidavit, testimony, or other materials permitted by the applicable procedural rules.

The judicial officer evaluates whether the information establishes sufficient grounds to believe that the identified person committed the offense described.

The precise procedure differs between federal and state courts.

The important constitutional principle is that the arrest warrant cannot simply be issued because police want to arrest someone. There must be a sufficient factual basis supporting probable cause.

Warrantless Arrests

A police officer may sometimes make an arrest without first obtaining an arrest warrant.

Warrantless arrests are an established part of U.S. criminal procedure, particularly when police have probable cause and the arrest occurs under circumstances in which the Constitution and applicable law permit immediate arrest.

For example, an officer who personally observes a person committing a crime may have immediate grounds for a warrantless arrest.

Similarly, officers may sometimes arrest a suspect without a warrant when probable cause exists and circumstances make immediate action legally permissible.

However, the existence of probable cause does not automatically answer every constitutional question concerning a warrantless arrest.

The place where the arrest occurs matters.

The circumstances matter.

State statutes matter.

And an arrest inside a private home raises additional Fourth Amendment concerns.

Arrests in Public Places

The constitutional rules governing an arrest in a public place differ from those governing entry into a private home.

When police have probable cause to arrest a person, a warrantless public arrest can generally be constitutionally permissible under federal law, subject to applicable statutory requirements and other constitutional limitations.

The Supreme Court addressed this issue in United States v. Watson, 423 U.S. 411 (1976), upholding a warrantless public arrest based on probable cause in the circumstances presented there.

The important distinction is between the authority to arrest a person in a public place and the authority to enter a private residence to make an arrest.

The Fourth Amendment treats the home as a particularly protected place.

Arrests Inside a Home

An arrest inside a person’s home raises a substantially different constitutional question.

In Payton v. New York, 445 U.S. 573 (1980), the Supreme Court held that the Fourth Amendment generally prohibits police from making a warrantless and nonconsensual entry into a suspect’s home to make a routine felony arrest when no exigent circumstances exist.

The principle is important because probable cause alone does not necessarily authorize police to enter a private home.

A valid arrest warrant may provide authority to enter the suspect’s residence when the constitutional requirements are satisfied and officers have reason to believe the suspect is inside.

Alternatively, exigent circumstances or valid consent may provide a basis for warrantless entry in appropriate cases.

The Supreme Court’s decision in Payton emphasizes the special constitutional protection given to the home. Payton v. New York — Cornell Law School Legal Information Institute

The Difference Between an Arrest Warrant and a Search Warrant

An arrest warrant and a search warrant are not the same legal instrument.

An arrest warrant authorizes the government to take a particular person into custody.

A search warrant authorizes police to search a specified place for particular categories of evidence or property.

Both generally involve probable cause, but the factual inquiry differs.

For an arrest warrant, the question concerns whether there is probable cause to believe that the identified person committed an offense.

For a search warrant, the question concerns whether there is probable cause to believe that evidence or contraband will be found in the specified location.

The two warrants should therefore not be treated as interchangeable.

Arrests Based on Probable Cause Without a Warrant

The existence of an arrest warrant is not always constitutionally necessary.

A police officer may sometimes make a warrantless arrest based on probable cause when the Constitution and applicable law permit it.

For example, an officer who observes a driver commit a serious traffic offense may have grounds for immediate arrest if state law authorizes that arrest.

Similarly, officers responding to a reported crime may develop probable cause against a particular suspect during their investigation.

The constitutional analysis therefore begins with probable cause but does not necessarily end there.

The officer must also have legal authority under the relevant federal or state law to make the warrantless arrest in the particular circumstances.

State Arrest Laws

Although the Fourth Amendment establishes constitutional limits, state law plays an important role in defining arrest authority.

States may establish rules concerning:

• when police may make warrantless arrests;
• which offenses permit warrantless arrest;
• arrest procedures;
• use of force;
• issuance and execution of warrants;
• summonses instead of arrests;
• booking procedures;
• appearance before a judge; and
• pretrial detention.

Federal constitutional law provides a minimum constitutional framework, but state law may provide additional protections.

Consequently, an arrest that is constitutionally permissible under federal law may still violate a more protective state statute or state constitutional provision.

Arrest by Warrant vs. Arrest Without a Warrant

The basic distinction can be summarized as follows:

Arrest With a Warrant	Warrantless Arrest
Judicial authorization is obtained beforehand	Police act without prior judicial authorization
Warrant is generally based on probable cause	Probable cause generally must exist at the time of arrest
Judge or magistrate reviews the supporting information	Officer may make the initial probable-cause determination
Provides judicial authorization in advance	Later judicial review becomes particularly important
Often used when immediate arrest is unnecessary	Common when immediate action is legally permitted

The difference does not mean that every warrantless arrest is constitutionally suspicious or that every warrant-based arrest is automatically lawful.

The validity of either type depends on the circumstances and applicable law.

When Does a Police Stop Become an Arrest?

A police encounter can progress through several stages.

An officer may initially approach a person voluntarily.

The officer may then conduct an investigative detention based on reasonable suspicion.

During the detention, additional facts may establish probable cause.

The officer may then arrest the person.

The transition is not always marked by a single verbal statement.

Courts consider the degree of restraint and the circumstances.

Factors can include:

• duration of the detention;
• use of handcuffs;
• physical force;
• transportation;
• confinement;
• display of weapons;
• number of officers;
• statements by police;
• location;
• degree of control over the person’s movement; and
• whether the detention remained investigative.

An officer cannot avoid arrest requirements simply by continuing to describe a custodial detention as a “stop.”

Handcuffs and Arrest

Handcuffs are commonly associated with arrest, but the presence of handcuffs does not automatically determine the legal classification of an encounter.

Police may sometimes use handcuffs temporarily during an investigative detention when reasonably necessary for safety or control.

Conversely, a person can be under arrest without being handcuffed.

The legal question is whether the totality of the circumstances demonstrates a sufficiently substantial restraint of liberty to constitute an arrest.

Once the encounter is properly characterized as an arrest, the constitutional requirements applicable to arrests must be satisfied.

Use of Force During an Arrest

Police may use force when making an arrest, but the Fourth Amendment imposes limits on the reasonableness of that force.

The Supreme Court’s decision in Graham v. Connor, 490 U.S. 386 (1989), established that claims involving force during an arrest or other seizure are generally analyzed under the Fourth Amendment’s objective-reasonableness standard.

Courts consider the circumstances confronting the officer at the time, including factors such as:

• the seriousness of the suspected offense;
• whether the person posed an immediate threat;
• whether the person was actively resisting; and
• whether the person was attempting to flee.

The analysis is fact-specific.

The constitutional question is generally not whether the officer’s conduct was ideal in hindsight, but whether the force used was objectively reasonable under the circumstances known to the officer at the time.

The Right to Know the Basis for an Arrest

The precise requirements for informing an arrested person of the reason for arrest can vary depending on the circumstances and jurisdiction.

An arrest warrant ordinarily identifies the offense or legal basis for the arrest.

In a warrantless arrest, the person may learn the basis through the officer’s explanation, charging documents, or subsequent judicial proceedings.

The Constitution and applicable law impose procedural requirements concerning notice, appearance, charging, and judicial review.

These requirements help prevent a person from being held indefinitely without being informed of the legal basis for the government’s action.

Miranda and Arrest

An arrest can create circumstances in which Miranda v. Arizona becomes relevant, but arrest and Miranda are not the same constitutional concept.

Miranda protections apply to custodial interrogation, not simply to every arrest.

Therefore, a person can be arrested without immediately being questioned.

Likewise, certain questioning can occur before a formal arrest, and Miranda may still become relevant if the person is in custody and subject to interrogation.

This distinction is important because:

The Fourth Amendment governs the legality of the arrest.

The Fifth Amendment’s Miranda doctrine governs certain custodial interrogation.

The two constitutional frameworks may interact, but they address different governmental conduct.

What Happens Immediately After an Arrest?

An arrest usually initiates a series of procedural steps.

Depending on the jurisdiction and circumstances, these may include:

1. transportation to a police facility;
2. booking;
3. identification and fingerprinting;
4. photographing;
5. inventory procedures;
6. processing of personal property;
7. charging or preparation of charging documents;
8. decisions concerning release or detention;
9. an initial court appearance; and
10. a judicial determination concerning probable cause where required.

The precise sequence varies between jurisdictions.

An arrest is therefore not the end of the criminal process. It is often the beginning of the formal custodial phase of the case.

Booking

Booking is the administrative process through which police formally record the person’s arrest.

It commonly involves:

• recording identifying information;
• taking fingerprints;
• taking photographs;
• recording the alleged offense;
• inventorying personal property; and
• entering the person into the detention system.

Booking procedures vary among jurisdictions.

Booking itself is not a determination of guilt.

It is an administrative consequence of being taken into custody.

Prompt Judicial Review

A person arrested without a warrant cannot ordinarily be held indefinitely without judicial oversight.

The Supreme Court’s decision in Gerstein v. Pugh, 420 U.S. 103 (1975), established that the Fourth Amendment generally requires a judicial determination of probable cause as a prerequisite to extended restraint of liberty following a warrantless arrest.

The Court recognized that the prosecutor’s own determination of probable cause is not, by itself, a substitute for the required judicial determination.

The exact procedures and timing vary, but the constitutional principle is important:

Warrantless arrest does not mean warrantless indefinite detention.

Judicial oversight must follow within the framework established by constitutional and applicable procedural law.

The 48-Hour Principle

The Supreme Court subsequently addressed the timing of probable-cause determinations in County of Riverside v. McLaughlin, 500 U.S. 44 (1991).

The Court held that a judicial determination of probable cause within 48 hours of a warrantless arrest generally satisfies the constitutional requirement, although the exact constitutional analysis depends on the circumstances.

A delay beyond 48 hours is not automatically unconstitutional in every imaginable circumstance, but the government bears significant constitutional burdens when detention continues without the required judicial determination.

This is an important distinction between the initial police decision to arrest and the later judicial supervision of continued detention.

Arrest and Bail

An arrest does not automatically determine whether the person will remain incarcerated until trial.

Depending on the offense and jurisdiction, the person may:

• be released on recognizance;
• receive a summons instead of continued detention;
• be released subject to conditions;
• post bail or bond;
• remain detained pending further proceedings; or
• fall under special rules governing particular offenses.

The constitutional and statutory rules governing pretrial release are distinct from the basic question of whether the original arrest was lawful.

For that reason, arrest, pretrial detention, and bail should be treated as separate stages of criminal procedure.

Arrest and the Presumption of Innocence

An arrested person remains legally presumed innocent unless and until the government proves guilt according to the applicable criminal standard.

Arrest does not change the burden of proof.

The prosecution remains responsible for proving the charged offense.

This principle is particularly important because an arrest can create a powerful social impression that a person has done something wrong.

Criminal procedure deliberately separates the government’s authority to arrest from the ultimate judicial determination of guilt.

Arrest and the Sixth Amendment Right to Counsel

An arrest does not necessarily mean that every Sixth Amendment right immediately applies in precisely the same way.

The Sixth Amendment right to counsel is generally connected to the initiation of adversarial judicial proceedings, and its application depends on the procedural posture of the case.

The right to counsel also has an important constitutional role during custodial interrogation through the Fifth Amendment’s Miranda framework.

These doctrines should not be collapsed into a single “right to a lawyer upon arrest.”

The precise source, timing, and scope of the right to counsel depend on the stage of the criminal proceeding and the type of governmental action involved.

Searches Incident to Arrest

A lawful arrest can have consequences for searches of the arrested person and certain areas within the constitutional scope of a search incident to arrest.

However, the doctrine is limited.

The Supreme Court’s decision in Arizona v. Gant, 556 U.S. 332 (2009), significantly defined the circumstances in which police may search a vehicle incident to an occupant’s arrest.

Digital devices present another important limitation. In Riley v. California, 573 U.S. 373 (2014), the Supreme Court held that police generally must obtain a warrant before searching the digital contents of a cell phone seized from an individual who has been arrested, subject to applicable exceptions.

These cases illustrate an important principle:

A lawful arrest does not automatically authorize every possible search.

The constitutional rules governing searches must still be applied separately.

What If the Arrest Was Unlawful?

If an arrest violates the Fourth Amendment or applicable law, several legal consequences may potentially follow.

A defendant may challenge:

• the legality of the arrest;
• evidence obtained as a consequence of the arrest;
• statements made during the resulting custody;
• searches conducted incident to the arrest; or
• continued detention.

The precise remedy depends on the nature of the violation.

An unlawful arrest does not necessarily mean that the defendant cannot be prosecuted for the underlying crime.

Similarly, an unlawful arrest does not automatically mean that every piece of evidence subsequently obtained must be excluded.

Courts may apply doctrines governing suppression, attenuation, independent source, inevitable discovery, or other recognized exceptions.

The constitutional violation and the appropriate remedy are therefore separate questions.

False Arrest

A false arrest is an arrest or detention made without lawful justification.

Cornell’s Wex materials describe false arrest as restraint or detention undertaken without probable cause, a valid arrest warrant, or another lawful basis for the asserted authority.

The concept can arise in both constitutional litigation and other forms of civil liability, depending on the circumstances and jurisdiction.

A person who is falsely arrested may potentially have claims under federal civil-rights law or state law, although the existence and viability of such claims depend on numerous factors.

This is distinct from the criminal case itself.

Civil Liability for Unlawful Arrests

An unlawful arrest can potentially give rise to civil litigation.

Under 42 U.S.C. § 1983, a person may in appropriate circumstances bring a civil-rights action against a state or local government official who, acting under color of state law, violates constitutional rights.

Fourth Amendment violations can therefore have consequences outside the criminal prosecution.

However, civil claims against police officers involve their own procedural requirements and defenses, including doctrines such as qualified immunity in appropriate cases.

The existence of a potentially unlawful arrest does not automatically establish civil liability.

Federal and State Differences

Arrest law is shaped by both federal constitutional principles and state or federal statutory law.

Federal cases are governed by the U.S. Constitution, federal statutes, the Federal Rules of Criminal Procedure, and federal judicial decisions.

State cases are governed by the U.S. Constitution together with the relevant state’s constitution, statutes, procedural rules, and judicial decisions.

States may impose greater protections than the federal constitutional minimum.

Therefore, questions such as:

• when police may make a warrantless arrest;
• whether a particular offense permits immediate arrest;
• when a summons must be used;
• how quickly a person must appear before a judge; and
• what procedures govern release

can differ significantly among jurisdictions.

A general constitutional explanation of arrest should therefore not be treated as a substitute for the law of a particular state.

Arrests in the Criminal Process

An arrest is one stage in a much larger sequence.

A simplified criminal process may look like:

Investigation → Reasonable suspicion → Investigative detention → Probable cause → Arrest → Booking → Initial appearance → Charging and pretrial proceedings → Trial or plea → Sentencing → Appeal

Not every criminal case follows this exact sequence.

A suspect may receive a summons rather than being arrested.

A warrant may be issued before police locate the suspect.

A person may voluntarily surrender.

A grand jury may return an indictment before the defendant is arrested.

Procedural variations are common.

The important point is that arrest is a transition point between investigation and formal custodial criminal proceedings, not the conclusion of the case.

A Practical Example

Suppose police investigate a burglary at a local business.

Security footage shows a person entering the building at approximately 2:00 a.m. A witness provides additional information identifying the suspected individual. Police investigate further and obtain evidence connecting a particular person to the offense.

At this point, officers may develop probable cause.

If the circumstances and applicable law permit a warrantless public arrest, officers may take the suspect into custody.

Alternatively, investigators may present their evidence to a judge and obtain an arrest warrant.

Suppose the suspect is then arrested in a public location.

The arrest must be supported by the required legal justification.

The person may then be transported for booking and brought before a judicial officer according to the applicable procedures.

If the suspect is questioned while in custody, Miranda issues may arise.

If police search the suspect or property, separate Fourth Amendment questions may arise.

The person may then be released, detained, or subjected to other pretrial procedures depending on the offense and jurisdiction.

This example demonstrates why arrest should not be viewed as one isolated event. It initiates a chain of constitutional and procedural consequences.

Arrests and the Balance Between Government Power and Individual Liberty

The power to arrest is essential to the functioning of a criminal justice system.

Without the ability to take suspected offenders into custody, police could not effectively prevent flight, protect victims, preserve public safety, or bring accused persons before the courts.

But arrest is also one of the government’s most serious intrusions on individual liberty.

A person may lose freedom of movement, employment, privacy, access to family, and control over daily life.

The constitutional requirement of probable cause therefore serves an important limiting function.

Government must have a sufficient factual basis before exercising this extraordinary power.

Judicial review provides an additional safeguard, particularly when a person has been arrested without a warrant.

Key Takeaways

Arrest is a central stage of criminal procedure and one of the most significant forms of governmental restraint.

The most important principles are:

1. An arrest is a governmental seizure involving a substantial restraint on a person’s freedom of movement.
2. The Fourth Amendment provides the principal constitutional framework governing arrests.
3. Probable cause is generally required for an arrest.
4. Probable cause is higher than reasonable suspicion but lower than proof beyond a reasonable doubt.
5. An arrest does not establish guilt.
6. An arrest warrant is judicial authorization to take a specified person into custody.
7. A warrant is not constitutionally required for every arrest.
8. Warrantless public arrests may be lawful when probable cause and applicable legal requirements are satisfied.
9. Entry into a person’s home to make a routine arrest raises additional Fourth Amendment requirements.
10. Under Payton v. New York, police generally may not make a warrantless, nonconsensual entry into a suspect’s home for a routine felony arrest absent exigent circumstances or another recognized basis.
11. A police stop can develop into an arrest when the degree of restraint increases and probable cause exists.
12. An arrest does not automatically authorize every search of the person, vehicle, home, or digital device.
13. A warrantless arrest is subject to subsequent judicial review.
14. Under Gerstein v. Pugh and County of Riverside v. McLaughlin, constitutional protections require timely judicial determination of probable cause following a warrantless arrest.
15. State law can impose additional requirements beyond the federal constitutional minimum.
16. An unlawful arrest may have consequences for evidence, statements, detention, and potential civil claims, although remedies depend on the circumstances.

Frequently Asked Questions

What is an arrest?

An arrest is a governmental seizure in which law enforcement uses legal authority to take a person into custody or substantially restrain the person’s freedom of movement because of suspected criminal activity.

Does police need probable cause to arrest someone?

Generally, yes. Probable cause is the principal constitutional standard governing arrests. The precise requirements for warrantless arrests also depend on the applicable federal or state law.

Is an arrest warrant always required?

No. Many arrests may lawfully occur without a warrant when probable cause exists and the circumstances permit a warrantless arrest.

What is the difference between an arrest and a police stop?

A police stop is generally a temporary investigative detention based on reasonable suspicion. An arrest is a substantially greater restraint of liberty and generally requires probable cause.

Can police arrest someone in public without a warrant?

Under federal constitutional law, a warrantless public arrest may generally be permissible when police have probable cause and applicable legal requirements are satisfied.

Can police enter someone’s home to make an arrest?

The rules are more restrictive. Under Payton v. New York, police generally cannot make a warrantless, nonconsensual entry into a suspect’s home to make a routine felony arrest when no exigent circumstances exist.

Does being arrested mean that someone is guilty?

No. An arrest is not a finding of guilt. It means that the government has sufficient legal grounds to take the person into custody. Guilt must be established through the criminal adjudication process.

Are Miranda rights required immediately upon arrest?

Not necessarily. Miranda warnings are generally required before custodial interrogation. Arrest and Miranda custody are related but distinct legal concepts.

What happens after an arrest?

Depending on the jurisdiction and circumstances, the person may be booked, processed, charged, released, detained, or brought before a judge for an initial appearance and judicial determination concerning probable cause and pretrial detention.

How quickly must an arrested person see a judge?

Constitutional requirements generally require a prompt judicial determination of probable cause following a warrantless arrest. Under County of Riverside v. McLaughlin, a determination within 48 hours will generally satisfy the Fourth Amendment requirement, although the precise rules and procedures vary.

Can an unlawful arrest cause criminal charges to disappear?

Not automatically. An unlawful arrest may affect the admissibility of evidence or give rise to other legal remedies, but it does not necessarily prevent the government from prosecuting the underlying offense.

Can a person sue because of an unlawful arrest?

Potentially. Depending on the circumstances, federal civil-rights law and state law may provide remedies for unlawful arrest. Such claims involve separate legal requirements and defenses.

Conclusion

Arrest is the point at which the government’s response to suspected criminal activity becomes a substantial restraint on individual liberty. Because of the seriousness of that intrusion, the Constitution generally requires probable cause before police may take a person into custody.

The law nevertheless distinguishes between different circumstances. A warrant may provide judicial authorization in advance, while a warrantless arrest may be constitutionally permissible when probable cause and the applicable legal requirements are satisfied. The rules become particularly protective when police seek to enter a private home to make an arrest.

An arrest also does not end constitutional scrutiny. Booking, questioning, searches, detention, judicial review, bail, and subsequent criminal proceedings each involve their own legal requirements.

The central principle is therefore straightforward:

Police may arrest a person when the law provides authority to do so and the required constitutional justification exists, but an arrest is not a determination of guilt.

The constitutional safeguards surrounding arrest exist precisely because the power to take a person into custody is one of the most consequential powers exercised by the criminal justice system.