IL POST cheat sheet

The criminal justice system has three main components: law enforcement, courts, and corrections; each operates at local, state, and federal levels.

Illinois has three tiers of law enforcement: municipal police, county sheriffs, and state agencies such as the Illinois State Police.

The Illinois Criminal Code (720 ILCS 5/) defines offenses and defenses; the Code of Criminal Procedure (725 ILCS 5/) governs arrest, search, and prosecution.

A crime requires actus reus (voluntary act or omission) and mens rea (mental state), except strict liability offenses.

The burden of proof in criminal cases is beyond a reasonable doubt; in civil cases it is preponderance of the evidence.

The exclusionary rule (Mapp v. Ohio, 1961) bars evidence obtained through unconstitutional searches or seizures from being used in criminal trials.

The chain of custody documents every person who handled evidence to ensure integrity and admissibility at trial.

Illinois law enforcement officers must complete state-certified basic training through the Illinois Law Enforcement Training and Standards Board (ILETSB).

720 ILCS 5/9-1 defines first degree murder: killing without lawful justification with intent, knowledge, or felony murder, or with strong probability of death or great bodily harm.

Second degree murder (720 ILCS 5/9-2) is a killing with provocation or unreasonable belief in self-defense; it is a Class 1 felony with a possible sentence of 4-20 years.

Battery (720 ILCS 5/12-3) is intentional or knowing causing of bodily harm or offensive contact; it is a Class A misdemeanor for a first offense.

Aggravated battery (720 ILCS 5/12-3.05) involves serious bodily harm, use of a deadly weapon, or special victim status and is a Class 3 felony.

Theft (720 ILCS 5/16-1) is knowingly obtaining or exerting unauthorized control over property with intent to permanently deprive; value determines the class.

Retail theft (720 ILCS 5/16-25) includes taking merchandise, altering price tags, or transferring merchandise to another container with intent to deprive.

Residential burglary (720 ILCS 5/19-3) is entering a dwelling without authority with intent to commit a felony or theft; it is a Class 1 felony.

Criminal trespass to a residence (720 ILCS 5/19-4) is entering or remaining in a residence without authority; it is a Class A misdemeanor.

An arrest requires probable cause that a person committed an offense; a warrant is not required for a felony committed in an officer's presence.

The Fourth Amendment protects against unreasonable searches and seizures and requires warrants based on probable cause, particularly describing place and persons or things to be seized.

The Fifth Amendment protects against compelled self-incrimination and double jeopardy; Miranda warnings are required before custodial interrogation.

The Sixth Amendment guarantees the right to counsel and a speedy trial; it attaches at the initiation of adversarial judicial proceedings.

The Fourteenth Amendment applies due process and equal protection to the states, incorporating most Bill of Rights protections against state action.

The exclusionary rule applies to evidence obtained in violation of the Fourth Amendment; the good-faith exception allows evidence when officers reasonably relied on a defective warrant.

The fruit of the poisonous tree doctrine excludes evidence derived from an unconstitutional search or seizure, unless attenuated or inevitable discovery applies.

Miranda custody exists when a reasonable person would not feel free to leave; interrogation includes express questioning or its functional equivalent.

The public safety exception allows limited questioning without Miranda when there is an immediate threat to public safety.

A search warrant must be supported by probable cause, describe the place to be searched and items to be seized, and be executed within a specified time, generally within 96 hours in Illinois.

A warrantless search is per se unreasonable unless it falls within a recognized exception: consent, search incident to arrest, plain view, exigent circumstances, automobile exception, or inventory.

Search incident to arrest allows a search of the arrestee's person and the area within immediate control (wingspan) for weapons and evidence.

The automobile exception allows a warrantless search of a vehicle if officers have probable cause to believe it contains contraband or evidence.

Consent must be voluntary and can be withdrawn at any time; officers may rely on apparent authority if a reasonable person would believe the consenting party has authority.

Terry v. Ohio (1968) permits a brief investigatory stop based on reasonable suspicion of criminal activity and a protective pat-down for weapons if officer safety requires.

An arrest requires probable cause; a warrantless arrest for a misdemeanor generally requires the offense to occur in the officer's presence, except for domestic violence offenses.

Illinois law requires officers to inform an arrestee of the reason for arrest and to take them before a judge without unnecessary delay, generally within 48 hours.

Community policing emphasizes partnership with residents, problem-solving, and organizational transformation to address crime causes.

The SARA model (Scanning, Analysis, Response, Assessment) is a structured problem-solving method used in community policing.

Directed patrol assigns officers to specific high-crime areas at specific times based on crime analysis data.

Hot spots policing focuses resources on small geographic areas with concentrated crime, supported by evidence of effectiveness.

Officers should conduct regular business checks, maintain visibility, and vary patrol routes to deter crime.

The broken windows theory holds that visible disorder and minor offenses, if unaddressed, lead to more serious crime.

Community engagement includes attending neighborhood meetings, foot patrols, and building trust with diverse populations.

Patrol officers must document all incidents, including field interviews and citizen contacts, in a timely and accurate manner.

The first responding officer must secure the scene, render aid, and preserve evidence; the scene should be secured with tape and a log.

Chain of custody must record every transfer of evidence, including date, time, from whom, to whom, and purpose.

Physical evidence includes fingerprints, DNA, trace evidence, weapons, and documents; each requires proper packaging to avoid contamination.

Biological evidence should be air-dried and packaged in paper, not plastic, to prevent mold and degradation.

Photograph the scene before moving anything; use overall, mid-range, and close-up photographs with scales.

Interviews should be conducted separately for witnesses and suspects; document verbatim statements and note demeanor.

Crime scene sketches should include measurements, compass direction, and a key to evidence locations.

The Illinois State Police Forensic Sciences Command operates regional laboratories for DNA, toxicology, and firearms analysis.

Illinois law requires a driver involved in a crash resulting in injury, death, or property damage over $1,500 to report the crash to police.

A traffic crash report must be completed for crashes involving injury, death, or property damage over $1,500, or when a vehicle is towed.

The three-second rule is a guideline for safe following distance under ideal conditions; increase distance in bad weather or at night.

Horizontal gaze nystagmus (HGN), walk-and-turn, and one-leg stand are standardized field sobriety tests used in DUI investigations.

Illinois implied consent law (625 ILCS 5/11-501.1) requires drivers to submit to chemical testing when arrested for DUI; refusal leads to license suspension.

DUI is defined in 625 ILCS 5/11-501: driving with a blood alcohol concentration of 0.08% or more, or under the influence of alcohol, drugs, or compounds.

Crash investigation includes documenting road conditions, weather, vehicle damage, skid marks, and witness statements.

Traffic stops require reasonable suspicion of a traffic violation; the stop must be reasonably related in scope and duration to the violation.

Graham v. Connor (1989) established the objective reasonableness standard for use of force, judged from the perspective of a reasonable officer on the scene.

Tennessee v. Garner (1985) prohibits the use of deadly force to prevent the escape of a fleeing suspect unless the officer has probable cause to believe the suspect poses a significant threat of death or serious physical injury.

The use-of-force continuum typically includes officer presence, verbal commands, soft empty-hand control, hard empty-hand control, intermediate weapons, and deadly force.

Illinois law (720 ILCS 5/7-5) allows the use of force likely to cause death or great bodily harm only to prevent death or great bodily harm to the officer or another.

The duty to intervene requires officers to stop excessive force by another officer and report it.

Officer safety principles include maintaining reactionary gap, using cover and concealment, and conducting high-risk stops with backup.

After any use of force, officers must render aid and document the incident thoroughly, including photographs of injuries.

Defensive tactics include handcuffing, takedowns, and control holds; the goal is to gain control while minimizing injury.

Crisis Intervention Team (CIT) training prepares officers to respond to individuals with mental illness or developmental disabilities.

De-escalation techniques include active listening, maintaining a safe distance, speaking calmly, and offering choices.

Illinois law (405 ILCS 5/) governs involuntary commitment; officers may take a person into custody for a mental health evaluation if they have reasonable grounds to believe the person is a danger to self or others.

Signs of excited delirium include agitation, profuse sweating, rapid breathing, and incoherent speech; it is a medical emergency requiring immediate EMS.

Officers should use time, distance, and cover to reduce tension and avoid unnecessary force.

When interacting with a person in crisis, avoid rapid movements, loud commands, and crowding; limit the number of officers in the immediate area.

The Americans with Disabilities Act (ADA) requires reasonable accommodations for individuals with disabilities during police interactions.

Suicide by cop occurs when a person intentionally provokes officers to use deadly force; recognizing the pattern can help de-escalate.

Reports should be written in the first person, past tense, and include who, what, when, where, why, and how.

Use clear, concise, and objective language; avoid opinions, conclusions, and jargon.

Document all elements of the offense to support probable cause and prosecution.

Include a detailed description of evidence, statements, and actions taken.

Reports should be completed before the end of shift and submitted promptly.

Testimony should be truthful, factual, and based on personal knowledge; review reports before testifying.

In court, address the judge as 'Your Honor' and avoid guessing; if you do not know, say so.

The Brady rule requires disclosure of exculpatory evidence to the defense.

The Law Enforcement Code of Ethics emphasizes service, integrity, and respect for constitutional rights.

Brady v. Maryland (1963) requires prosecutors to disclose exculpatory evidence to the defense.

Illinois law (50 ILCS 725/) establishes the Illinois Law Enforcement Officer Bill of Rights, governing investigations of officers.

Civil rights violations under 42 U.S.C. § 1983 allow civil suits against officers acting under color of law for constitutional violations.

Qualified immunity protects officers from liability unless they violate clearly established statutory or constitutional rights of which a reasonable person would have known.

The duty to intervene and report misconduct is an ethical and legal obligation.

Officers must avoid conflicts of interest, including accepting gifts or favors that could influence their duties.

Truthfulness is essential; dishonesty can lead to decertification by the Illinois Law Enforcement Training and Standards Board.

The Juvenile Court Act (705 ILCS 405/) governs delinquency proceedings; the focus is rehabilitation rather than punishment.

A juvenile is generally defined as a person under 18 years of age in Illinois.

Juveniles have Miranda rights; custody and interrogation must consider age and maturity.

Illinois law requires a parent or guardian to be notified when a juvenile is taken into custody.

Special populations include individuals with mental illness, developmental disabilities, and limited English proficiency; officers should use interpreters and accommodations.

The Illinois Juvenile Justice Commission oversees juvenile justice policies and programs.

Status offenses (e.g., truancy, running away) are offenses only because of the person's age.

Juvenile records are generally confidential but may be accessed by certain authorized parties.

The first step in any emergency is to ensure scene safety before rendering aid.

CPR for adults: 30 chest compressions followed by 2 rescue breaths, at a rate of 100-120 compressions per minute.

For severe bleeding, apply direct pressure and use a tourniquet if pressure fails and the bleeding is life-threatening.

The Heimlich maneuver (abdominal thrusts) is used for conscious choking adults and children over 1 year.

For an unconscious choking victim, begin CPR and check the mouth for visible objects; do not perform blind finger sweeps.

An AED should be applied as soon as available and used according to voice prompts.

For suspected overdose, administer naloxone (Narcan) if available and trained.

The emergency response sequence is: scene safety, check responsiveness, call 911, provide care, and document.