What is required to make an arrest without a warrant?

To make an arrest without a warrant, probable cause is essential. This legal standard requires that law enforcement officers have reasonable grounds to believe that a person has committed a crime. Probable cause is based on the facts and circumstances known to the officer at the time of the arrest, which must be sufficient to lead a reasonable person to conclude that an individual is involved in criminal activity.

In contrast, favorable witness testimony alone does not establish the necessary grounds for an arrest without a warrant, as it is just one piece of information that needs to be evaluated alongside other evidence. Immediate evidence of a crime might be compelling, but probable cause encompasses a broader assessment of the totality of the circumstances, rather than solely relying on direct evidence observed at that moment. A signed affidavit, while potentially useful in seeking a warrant, is not applicable in the context of warrantless arrests as it pertains to pre-arrest procedures rather than the justification needed at the time of arrest.

Thus, the requirement of probable cause is vital because it ensures that arrests are made based on a reasonable belief that a crime has been committed, protecting individual rights and maintaining legal standards of law enforcement.