Many people believe that the police must have an arrest warrant to arrest someone for a crime. This belief may come from television crime dramas, where it is common to see criminal detectives working with a judge to obtain an arrest warrant for the arrest of a suspect. There are, however, several instances when the police can arrest someone without an arrest warrant.
What is an arrest?
An arrest is when a law enforcement officer takes a person into custody and that person is not free to leave the custody of the police. A person is considered to be under arrest as soon as the law enforcement officer informs the person that they are under arrest.
What is probable cause?
The Supreme Court defines probable cause as “where the facts and circumstances within the officers' knowledge, and of which they have reasonably trustworthy information, are sufficient in themselves to warrant a belief by a man of reasonable caution that a crime is being committed.” In short, if a law enforcement officer believes that a crime is being committed or has been committed, they have probable cause and can place the person under arrest.
What is an arrest warrant?
An arrest warrant refers to an authorization provided by a judge for a law enforcement officer to arrest and detain an individual, ultimately delivering the person to the court. For an arrest warrant to be legal, the arrest warrant must demonstrate all of the following:
For a law enforcement officer to place someone under arrest, the officer must have probable cause or an arrest warrant. Note that whether the officer has an arrest warrant or not, probable cause is a key factor in allowing that officer to place someone under arrest.
When can an officer place a person under arrest?
1. The law enforcement officer observes a crime.
A law enforcement officer can place someone under arrest without a warrant if they observe the person committing a crime.
For example, take a police officer and their partner, who are out on patrol. They receive a report about a domestic disturbance, and they proceed to the address provided by their dispatcher. Upon arriving at the residence, they observe a man and woman fighting in the front yard. As they drive up, they see the man striking the woman with his fists.
The police officers have the authority to place the man under arrest because they observed him physically striking the woman, which constitutes probable cause that the crime of battery has occurred.
2. The law enforcement officer has probable cause to believe that a crime has been committed.
A law enforcement officer can place someone under arrest if they have probable cause that a crime has occurred, even if they did not witness the crime.
Let us again take the example of a police officer and their partner who are out on patrol. And again, the officers receive a report about a domestic disturbance and proceed to the address provided by their dispatcher. Upon arriving at the residence, they observe a man and woman in the front yard. The woman has visible cuts and bruises on her face, and informs the officers that the man struck her. The man claims that he did not strike her, but the officers observe cuts and bruises on his knuckles.
The police officers have the authority to place the man under arrest because they have probable cause that the crime of battery has occurred. Although the officers did not see the man strike the woman, the observable evidence—the statement by the woman, the cuts and bruises on the woman’s face, and the cuts and bruising on the man’s hands—are sufficient evidence that a crime has been committed and that the man was likely the perpetrator of the crime.
3. The law enforcement officer has an arrest warrant.
A law enforcement officer can place someone under arrest if they have a warrant for the arrest of that person.
For example, a woman enters a police station and tells the officers that she was beaten by her boyfriend. She has cuts and bruises on her face, which are observed by the officers. She also provides the officers with the name of her boyfriend, a physical description of him, and the address at which he lives.
The police officers can provide the information to a judge, who can use it to issue an arrest warrant. The information provided by the woman is sufficient for the judge to complete the required components of the arrest warrant.
With the arrest warrant, police officers can legally go to the boyfriend’s place of residence and enter it without his permission in an attempt to locate and arrest him. The physical description helps the officers identify and arrest the correct individual.