Criminal Law and Criminal Procedure
Two different questions
Criminal law asks whether conduct satisfies the elements of an offense. Criminal procedure asks whether the government acted lawfully while investigating and prosecuting. Exam questions frequently blend them, so separate them: first identify the offense and its elements, then test the police action against constitutional rules.
Concepts you must understand
- Elements of an offense: act, mental state (intent, knowledge, recklessness, negligence), causation, and any result or attendant circumstance. If one element is missing, the offense is not complete.
- Searches and seizures: the Fourth Amendment requires reasonableness. Warrantless searches generally need an exception: consent, search incident to arrest, exigency, plain view, automobile, or inventory.
- Stop versus arrest: a brief investigative detention requires reasonable suspicion; a full arrest requires probable cause.
- Interrogation and Miranda: custody plus interrogation triggers the warning; spontaneous statements are not interrogation.
- Identification procedures: lineups and photo arrays must not be impermissibly suggestive.
- Arizona-specific offenses include DUI, extreme and aggravated DUI, and trafficking in stolen property; know that aggravating factors raise the charge level.
Traps in questions
Distractors swap the standards: offering probable cause where reasonable suspicion is required, or vice versa. Another trap is a search that seems fine because evidence was found; the question is whether the search was lawful, not whether it was fruitful. Also watch for consent that was obtained by coercion or withdrawn mid-search.
Worked example
An officer stops a car for a burned-out taillight, smells alcohol, and asks the driver to step out. Is that lawful? Yes. The equipment violation supports the stop, and the odor plus contact observations supply reasonable suspicion, and often probable cause, for the impaired-driving investigation. The trap answer says the stop was invalid because the taillight was minor; minor violations still justify a stop.
Rule of thumb
Name the standard first (reasonable suspicion, probable cause, or warrant), then match the facts to it.