Any time a person is arrested, whether pursuant to a warrant, or for an offense committed in the presence of a cop, police are required to justify the arrest in a written sworn document. This document is then presented to a judge/magistrate either before arrest (in the case where an arrest warrant is obtained) or following arrest (for an offense committed in the presence of police.) The judge/magistrate then reviews the sworn statement of the officer to determine whether probable cause exists to believe a criminal offense has been committed.

If the judge determines that probable cause DOES NOT exist to support the officer’s belief that an offense has been committed, no warrant will issue (or, in the case where the person has been arrested for an offense in view of the officer, the person is released.) This happens very rarely—but it does happen!

More often than not, however, police are able to meet the low standard of probable cause. If a judge determines probable cause has been proven by the sworn statements in the affidavit (and not by anything outside of the affidavit—i.e., not by additional, unsworn statements made by the cop when he is presenting the affidavit to the judge), justification for the arrest exists (or an arrest warrant issues.)

Anytime after the person has been arrested (or after the warrant has been served and the person is in custody), the affidavit of probable cause becomes a public document that can be acquired by anyone (usually by a person’s lawyer.) Some lawyers never bother to attempt to obtain the affidavit of probable cause (!!!) This is poor lawyering, to be sure. The affidavit of probable cause contains valuable information about what the police knew in advance of the arrest if an informant was relied on, what evidence will exist and can be acquired when the case is filed, what evidence exists that will NOT be turned over but can be independently acquired by the lawyer, etc. Additionally, it provides an early summary of what the police will claim happened (the narrative that will be relied on by the State and by police at trial.)