Legal Authority, Use of Force, and Criminal Law
Foundations of Guard Authority
A security guard's authority comes from two sources: the property owner's delegation of rights and the same law that binds every citizen. A guard is generally not a police officer and rarely has powers of arrest beyond citizen's arrest statutes. Understand the distinction between detention (brief, reasonable, investigative) and arrest (taking a person into custody against their will). Know your jurisdiction's citizen's arrest rules: typically an arrest is lawful only for a felony committed in your presence, or a misdemeanor breach of the peace committed in your presence, followed by prompt delivery to police.
Use of Force
Force must be proportional, necessary, and objectively reasonable under the circumstances. Deadly force is almost never justified for a guard protecting property. The force continuum runs from presence and verbal commands through soft empty-hand control to hard empty-hand control, with weapons reserved for imminent threats of serious harm. Trap: questions often describe a fleeing shoplifter and ask if you may tackle them. Answer: no - force must match the threat, and property alone rarely justifies injury risk.
Criminal Law Concepts
Know the elements of common offenses: theft requires taking with intent to permanently deprive; burglary requires unlawful entry with intent to commit a crime; assault is the threat, battery is the contact. Know mens rea (intent) versus actus reus (the act). Trap: questions conflate detention with arrest, or confuse a civil trespass with a criminal offense.
Rule of Thumb
Use the "Reasonable Guard" test: would a trained guard, facing the same facts, have used the same force? If you must explain it in court, was the force the minimum needed? When in doubt, de-escalate, call police, and document.