When Is an Arrest a Legal Arrest?

The judge will deny the warrant if they do not believe probable cause exists. If the judge determines probable cause exists, they may issue the arrest warrant. In that case, the police may take the suspect into custody and arrest them.

Most people are somewhat nervous during an encounter with the police. You might not know what to say. You don't want to say or do the wrong thing. You may not trust that the police are talking to you for the reasons they said. Are the police just questioning you? Or are they arresting you?

This article explains what it means for police officers to arrest someone. Specifically, it covers what an arrest is, when it occurs, and the requirements for a legal arrest.

What Is an Arrest?

Generally, an arrest occurs when someone in authority restrains or seizes someone in connection with a crime. Typically, it involves a police officer restraining someone such that a reasonable person would believe they were not free to leave, given the circumstances. Therefore, if someone acting under legal authority restrains your freedom of action, they have likely arrested you.

Generally, there are three ways law enforcement can legally arrest a person. These include:

  • A law enforcement officer personally observes a person commit a crime
  • A law enforcement officer has probable cause to believe a person committed or is about to commit a crime
  • Law enforcement obtains a valid arrest warrant to arrest a person

The above definition of an arrest raises many questions. For example, under what circumstances would a reasonable person feel they were not free to leave? Who has the legal authority to arrest someone? How does law enforcement determine they can legally arrest someone?

Why Does It Matter Whether an Arrest Has Occurred?

Determining when law enforcement arrests a suspect is important for several reasons. The U.S. Constitution grants fundamental rights to arrestees. Generally, these rights only take effect once law enforcement arrests someone.

The Fourth Amendment provides fundamental rights to arrestees. For example, once an arrest occurs, a law enforcement officer may perform a search incident to the arrest. Additionally, a court may exclude from the arrestee's criminal case evidence seized in violation of the Fourth Amendment.

The Fifth Amendment provides suspects the right against self-incrimination and the right to counsel during a custodial interrogation. Before police can begin their custodial interrogation of a suspect, they must apprise the suspect of these rights. They do so by reading the suspect their Miranda rights.

The Sixth Amendment provides, among others, the right to counsel during a criminal case. The court will appoint a public defender if the defendant cannot afford an attorney.

A criminal suspect's constitutional rights are perhaps the most essential rights within the criminal justice system. These rights typically don't apply until the government arrests the suspect. Therefore, it is critical to understand when someone is under arrest rather than just stopped by the police.

Is a Police Detention an Arrest?

No, police detention is not necessarily an arrest. But, if the police detain you, they may gather enough evidence during the detention to arrest you.

Generally, police detention refers to when police stop a person and inform them they cannot leave. A stop is not necessarily an arrest. Instead, a stop may lead to an arrest. The stop itself, though, is not an arrest.

Can a Police Stop Lead to an Arrest?

Yes, a police stop can lead to an arrest. Nothing prevents a police officer from speaking to a person under ordinary circumstances. The law allows police to ask you questions. But suppose a person is uncomfortable answering. What are their obligations? Do they have to answer? Can they walk away?

A person is generally not required to answer police questions. They can decline to answer and ask to leave. Often, police question a person and release them.

Generally, if the police officer says a person cannot leave, they have been detained. The police may detain a person in a public or private area if they have reasonable suspicion to believe that person has been involved in a crime. But, at that point, law enforcement has not arrested them.

During the detention, the police may look for evidence that would give them probable cause to make an arrest. If, as a result of questioning, the police believe a suspect may be involved in a crime, they may choose to arrest them. They must state the arrestee's charges and read their rights if they decide to arrest. If they do not read the arrestee their rights and continue to question them while they are under arrest, their statements may be excluded from trial.

An arrest occurs when a law enforcement officer restricts the person's freedom of action. Typically, this involves taking the suspect into police custody.

Who Can Make a Legal Arrest?

Police officers can make an arrest if they have an arrest warrant. Generally, the warrant requirement applies to any arrest. There are exceptions to the requirement, though. In general, the police may arrest without a warrant if they have probable cause that the suspect committed a felony.

Sometimes, a private citizen can make an arrest. When and how it is allowed varies by state law. For example, Minnesota law allows a private person to arrest another:

  • For a public offense committed or attempted in the arresting person's presence
  • When the person arrested has committed a felony, although not in the arresting person's presence
  • When a felony has been committed, and the arresting person has reasonable cause for believing the person arrested to have committed it

Therefore, the arrestor does not necessarily need to be affiliated with a law enforcement agency to make a valid arrest.

Arrest Warrants

An arrest warrant is a court order authorizing law enforcement to arrest someone. Law enforcement must obtain a warrant from a neutral judge or magistrate. The warrant must be based on a showing of probable cause.

What Is Probable Cause for an Arrest?

The Fourth Amendment of the U.S. Constitution requires that the police have probable cause before they arrest someone or search and seize their property. The Fourth Amendment states:

"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."

Probable cause is based on factual evidence, not suspicions or hunches. Law enforcement may show probable cause using the following:

  • Observation alone (sight, smell, sound): This includes not only observed evidence of a crime but also observations of a familiar pattern of criminal activity, such as when an officer sees a car circling an area repeatedly or when someone is flashing their headlights.
  • Witnesses, victims, and informants
  • Police expertise, training, and experience: For example, a police officer may recognize gang signs, the tools used for committing certain crimes, or movements and gestures that indicate criminal activity
  • The collective knowledge of police: For example, an arresting officer may know of evidence their colleagues or agency collected
  • Circumstantial evidence that indirectly indicates that a crime has occurred, such as a broken window
  • Reasonable inferences that can be drawn from the available evidence

There may be other ways a police officer can obtain probable cause. Once the police officer believes they can show probable cause, they try to obtain an arrest warrant from a judge.

Who Decides Whether an Officer Had Probable Cause?

Probable cause is a crucial element of police procedure. When the police ask a judge for an arrest warrant, the judge first determines whether their evidence is sufficient to give probable cause that the warrant's subject committed a crime.

In the case of a warrantless arrest, a judge, justice of the peace, or bail commissioner will subsequently rule on whether probable cause for the arrest existed. An officer could have a reasonable good faith belief that they had probable cause, but a judge could later determine that there was, in fact, no probable cause.

An arrestee can challenge an arrest for a lack of probable cause. If they prevail, the court may release the suspect from custody.

How Much Evidence Is Needed to Establish Probable Cause?

Determining whether evidence meets the standard of probable cause is more art than science. Whether it exists depends heavily on the circumstances.

It may best be understood by what it is not. Probable cause is less than a preponderance of the evidence — a standard used to prove certain facts in court — but more than a reasonable suspicion based on objective facts. There must be some evidence to support a determination of probable cause; it cannot be based on a hunch.

The probable cause standard allows judges to balance law enforcement's responsibility to protect citizens from crime against the rights of citizens not to be harassed by the police.

A judge determines whether probable cause exists by:

  • Examining the facts presented and any reasonable inferences that can be drawn from those facts
  • Based upon the totality of the circumstances
  • Under the auspices of common sense

The sum of this must amount to a fair probability that the suspect committed a crime and that the arrested person is the one who committed the crime.

Was Your Arrest Legal? Get Help From an Attorney

If you or someone you know has been arrested, time is of the essence. You may be able to fight the constitutionality of your arrest on the grounds of probable cause. Talk to an experienced criminal defense attorney in your area. A criminal defense lawyer can provide helpful legal advice regarding the following:

If you are facing jail time or the government will file charges against you, do not delay contacting a criminal defense attorney near you.

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