A detective tells a landlord he is the tenant's brother so that the landlord will let him into the building. Under 720 ILCS 5/21-3 this is:720 ILCS 5/21-3
A man tells a homeowner he is from the gas company so that she will let him in, and he means to steal inside. Which offense does 720 ILCS 5/19-3 name?720 ILCS 5/19-3
After an arrest without a warrant in Illinois, what must the person making the arrest tell the person arrested, under 725 ILCS 5/103-1?725 ILCS 5/103-1
An agency owner knowingly keeps an employee who illegally uses an eavesdropping device on cases. In 720 ILCS 5/14-1 the owner is:720 ILCS 5/14-1
An Illinois detective secretly records a private conversation that she herself takes part in. Under 720 ILCS 5/14-2 this is eavesdropping unless:720 ILCS 5/14-2
Besides a Firearm Owner's Identification Card, what must an Illinois detective hold to carry a firearm in the performance of duties, under 225 ILCS 447/35-35?225 ILCS 447/35-35
Besides unreasonable searches and seizures, what does Article I, Section 6 of the Illinois Constitution secure the people against?Illinois Constitution, Article I, Section 6
Show all 60 questions (53 more)
Federal and state law, continued
How does 720 ILCS 5/14-4 grade a first offense of eavesdropping in Illinois?720 ILCS 5/14-4
Under 720 ILCS 5/21-3, entering open land of another becomes criminal trespass after the person has received:720 ILCS 5/21-3
Unless another period applies, how long after an Illinois misdemeanor may a prosecution be commenced under 720 ILCS 5/3-5?720 ILCS 5/3-5
What does "surreptitious" mean in the Illinois eavesdropping article, 720 ILCS 5/14-1?720 ILCS 5/14-1
What must a complaint for an Illinois search warrant show under 725 ILCS 5/108-3?725 ILCS 5/108-3
What separates burglary under 720 ILCS 5/19-1 from simply being in a building without authority?720 ILCS 5/19-1
When may a private person making a lawful arrest in Illinois use force likely to cause death or great bodily harm, under 720 ILCS 5/7-6?720 ILCS 5/7-6
Which is an element of perjury under 720 ILCS 5/32-2?720 ILCS 5/32-2
Which of these does the Sixth Amendment to the United States Constitution guarantee the accused in a criminal prosecution?U.S. Constitution, Amendment VI
Which of these offenses is a "forcible felony" as 720 ILCS 5/2-8 defines the term?720 ILCS 5/2-8
Which right does the Fifth Amendment to the United States Constitution give a person in a criminal case?U.S. Constitution, Amendment V
Licensing and practice requirements 10
225 ILCS 447/15-25 sets what first training for a detective agency's newly registered staff?225 ILCS 447/15-25
A firm offers computer forensics services in Illinois. When is it exempt from private detective licensure under 225 ILCS 447/15-5?225 ILCS 447/15-5
An applicant has a felony conviction. When does 225 ILCS 447/15-10 allow an Illinois private detective license?225 ILCS 447/15-10
An Illinois agency loses its licensee-in-charge. For how long is a temporary certificate of authority valid under 225 ILCS 447/15-15?225 ILCS 447/15-15
An Illinois applicant has not passed the examination 3 years after filing. What does 225 ILCS 447/10-35 provide?225 ILCS 447/10-35
An Illinois private detective takes a case while the license is on inactive status. Under 225 ILCS 447/10-25 this is:225 ILCS 447/10-25
How much annual training does 225 ILCS 447/15-25 require of an Illinois private detective, and how long is the log kept?225 ILCS 447/15-25
How much of the experience requirement does a baccalaureate degree in law enforcement cover for an Illinois private detective applicant?225 ILCS 447/15-10
How old must a person be to qualify for an Illinois private detective license under 225 ILCS 447/15-10?225 ILCS 447/15-10
What experience does 225 ILCS 447/15-10 ask of an Illinois private detective applicant?225 ILCS 447/15-10
Detective practices: gathering information 13
According to the federal crime scene guide, what is the first priority of the first person to respond to a scene?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section A
Before a witness views a lineup, what does the federal eyewitness evidence guide say the witness must be told about the person who committed the crime?NIJ, Eyewitness Evidence: A Guide for Law Enforcement, Section V.B
During the first walk-through of a scene, how does the federal crime scene guide say to avoid contaminating it?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section B
How does the federal crime scene guide say to handle the witnesses found at a scene?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section A
How many fillers does the federal eyewitness evidence guide call for in a photo lineup?NIJ, Eyewitness Evidence: A Guide for Law Enforcement, Section V.A
How should an item of evidence be photographed before it is collected, according to the federal crime scene guide?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section C
In what order does the federal crime scene guide say to collect evidence?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section C
Once scene boundaries are set, what does the federal crime scene guide say to document about people?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section A
What does the federal crime scene guide say to do with a firearm before it is made safe for transport?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section C
What does the federal crime scene guide say to record when an item of evidence is collected?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section C
What three ranges of photographic coverage does the federal crime scene guide call for at a scene?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section C
Which evidence does the federal crime scene guide say to secure immediately from the vicinity of a scene?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section C
Why does the federal crime scene guide say to set scene boundaries beyond the first apparent scope of the scene?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section A
Detective practices: case management 9
According to the federal crime scene guide, what does the scene assessment by the investigator in charge determine?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section B
How does the federal fire and arson scene guide say to package an item of fire debris evidence?NIJ, Fire and Arson Scene Evidence, Section D
In what direction does the federal fire and arson scene guide say to make the first tour of a fire scene?NIJ, Fire and Arson Scene Evidence, Section B
What does the final survey of a scene confirm, according to the federal crime scene guide?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section D
When a team is assembled to process a scene, what does the federal crime scene guide say to document?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section C
When does the federal crime scene guide place the scene debriefing?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section D
Which legal question does the federal crime scene guide tell the investigator in charge to evaluate before the scene is processed?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section B
Which of these belongs in the crime scene case file, according to the federal crime scene guide?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section D
Why does the federal fire and arson scene guide say to avoid fuel-powered tools at a fire scene?NIJ, Fire and Arson Scene Evidence, Section D
Detective practices: analysis, reporting and presentation 10
A detective sends a written records request to an Illinois city. How long does the city have to comply or deny under 5 ILCS 140/3?5 ILCS 140/3
A seized laptop may also carry fingerprints. In what order does the federal electronic crime scene guide put the work?NIJ, Electronic Crime Scene Investigation, Second Edition, Chapter 6
A witness picks someone at a showup. How does the federal eyewitness evidence guide say to record how certain the witness is?NIJ, Eyewitness Evidence: A Guide for Law Enforcement, Section IV.B
An Illinois public body does not answer a written records request within 5 business days and does not extend the time. Under 5 ILCS 140/3 the silence is:5 ILCS 140/3
An untrained person finds a suspect's computer switched on. What does the federal electronic crime scene guide say about the keyboard and mouse?NIJ, Electronic Crime Scene Investigation, Second Edition, Introduction
May an Illinois public body make a records requester say why the records are wanted, under 5 ILCS 140/3?5 ILCS 140/3
Which of these does the federal crime scene guide say an investigator's scene notes should record?NIJ, Crime Scene Investigation: A Guide for Law Enforcement, Section C
Which packaging does the federal electronic crime scene guide rule out for digital evidence?NIJ, Electronic Crime Scene Investigation, Second Edition, Chapter 6
Which tools does the federal electronic crime scene guide warn against when digital devices are collected?NIJ, Electronic Crime Scene Investigation, Second Edition, Chapter 2
Why does the federal electronic crime scene guide say to wrap a seized cell phone in radio frequency-shielding material?NIJ, Electronic Crime Scene Investigation, Second Edition, Chapter 2
How this list was compiled: Illinois Compiled Statutes on the Illinois General Assembly site (https://www.ilga.gov/Legislation/ILCS/Chapters): the Private Detective, Private Alarm, Private Security, Fingerprint Vendor, and Locksmith Act of 2004 (225 ILCS 447), sections of the Criminal Code of 2012 (720 ILCS 5), the Code of Criminal Procedure of 1963 (725 ILCS 5), the Firearm Owners Identification Card Act (430 ILCS 65) and the Freedom of Information Act (5 ILCS 140), and Article I of the Illinois Constitution; Amendments V and VI to the United States Constitution in the National Archives transcript (https://www.archives.gov/founding-docs/bill-of-rights-transcript); and four National Institute of Justice guides: Crime Scene Investigation: A Guide for Law Enforcement (2000; https://www.ojp.gov/pdffiles1/nij/178280.pdf), Eyewitness Evidence: A Guide for Law Enforcement (1999; https://www.ojp.gov/pdffiles1/nij/178240.pdf), Electronic Crime Scene Investigation: A Guide for First Responders, Second Edition (2008; https://www.ojp.gov/pdffiles1/nij/219941.pdf) and Fire and Arson Scene Evidence: A Guide for Public Safety Personnel (2000; https://www.ojp.gov/pdffiles1/nij/181584.pdf). All read on October 16, 2026. The five topics and their shares follow the examination information the testing service publishes for the Illinois Department of Financial and Professional Regulation (https://www.continentaltesting.net/File/Download?name=DETSECGDE&v=1). Licence: Own work. Every question, wrong choice and explanation was written for this site from the public texts named under "source". Nothing comes from the Illinois examination, from the sample questions in the examination information, from the textbooks it lists or from a prep publisher.
How it works
This unofficial Illinois private detective exam study guide works by questions: 60 of our own, split like the examination between law, licensing and detective practices. Not affiliated with the Illinois Department of Financial and Professional Regulation.
Read the full guide
What the Illinois examination covers
The examination information published for the Department lists 75 questions: 23 on federal and state law, 12 on licensing and practice requirements and 40 on detective practices. This bank keeps those shares.
Where the questions come from
Law and licensing questions cite the Illinois Compiled Statutes, the Illinois Constitution and the Bill of Rights. Practice questions cite four National Institute of Justice guides, on crime scenes, eyewitness evidence, digital evidence and fire scenes, and the Illinois Freedom of Information Act.
What is left out
The real detective practices section is keyed to a commercial textbook; nothing here is taken from it. Surveillance technique and the rules in 68 Ill. Adm. Code 1240 are not asked.
Recording a private conversation you are part of still needs the consent of all other parties (720 ILCS 5/14-2).
Three years of full-time experience in the last five; a bachelor's degree in a related field counts for two (225 ILCS 447/15-10).
Eight hours of training a year, logged for at least five years (225 ILCS 447/15-25).
Questions and answers
How many questions are on the Illinois private detective exam?
75, with 90 minutes to finish, according to the examination information. Exam mode here is 50 questions in 60 minutes.
What is the passing score for the Illinois private detective exam?
70. The examination information says candidates who score 70 or higher receive a pass notice and an application for licensure, and those below 70 a failure notice and an application for re-examination.
How many times can you take the Illinois private detective exam?
The examination information sets no limit while your experience and application remain valid. By statute an application is denied if the examination is not passed within 3 years of filing; a new application may then be made (225 ILCS 447/10-35).
How often is the Illinois private detective exam given?
At least twice a year by statute (225 ILCS 447/10-35). On October 16, 2026 the testing service's page for the examination listed three dates through June 2027 and a fee of $298.
What are the requirements to be a private detective in Illinois?
Age 21, good moral character, 3 years of full-time investigative experience in the last 5, fingerprints, general liability insurance and a passed examination. A felony bars a license until 10 years after full discharge (225 ILCS 447/15-10).