Final answer:
Police file an affidavit of probable cause before a person is arrested to present evidence and establish probable cause to a judge.
Step-by-step explanation:
Police file an affidavit of probable cause before a person is arrested to present evidence and establish probable cause to a judge in order to obtain an arrest warrant.
An affidavit is a written statement made under oath and penalty of perjury, detailing the facts and circumstances that support the belief that a crime has been committed by the individual to be arrested.
By filing an affidavit of probable cause, police provide the court with the necessary information to determine if there is enough evidence to justify the arrest.
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