Criminal Law and Civil Liability (Arrest, Detention, Search, Use of Force)
What this domain tests
Criminal law and civil liability: arrest, detention, search, and use of force. Illinois law governs when a private guard may interfere with a person, how much force is allowed, and what civil claims follow from mistakes. The exam tests statute-based limits, not “officer discretion.”
Core rules
- Defense of person (720 ILCS 5/7-1): force, including deadly force, only when reasonably necessary to prevent imminent death or great bodily harm. Defense of property (720 ILCS 5/7-3) does not authorize deadly force.
- Detention must be based on reasonable grounds, limited in scope, reasonable in duration, and conducted in a reasonable manner. The shopkeeper’s privilege for retail theft allows reasonable detention to investigate, recover property, and summon police-not punishment or a full search.
- Private searches: the Fourth Amendment binds government actors; a private guard can still commit trespass, battery, or invasion of privacy. Search bags only with consent, lawful arrest authority, or an immediate safety need; use gradual, least-intrusive steps.
- Civil exposure: false arrest/false imprisonment, battery, assault, malicious prosecution, defamation, negligence, and negligent hiring/training. Respondeat superior can reach the employer.
Worked example
A guard sees a shopper conceal a $60 item and pass the last point of sale. The guard says, “I need to speak with you about unpaid merchandise,” escorts the person to an office, calls police, and waits 12 minutes. Reasoning: reasonable grounds exist, the detention is brief and private, and the purpose is investigation/recovery. If the guard instead handcuffs the person, announces theft to the crowd, and searches a purse without consent, the privilege may be lost and false imprisonment/battery claims arise.
Traps
- Using deadly force to protect property.
- Treating “probable cause” as a police-only standard and ignoring state citizen-arrest rules.
- Prolonging detention after police arrive or after the basis disappears.
- Searching to humiliate rather than to recover evidence.