- The IL-PD exam has exactly 3 domains across 75 questions in 90 minutes: Federal & State Law (23), Licensing & Practice Requirements (12), Detective...
- Detective Practices is the largest domain and splits into Gathering Information (16), Case Management (12), and Analysis, Reporting & Presentation (12)...
- Passing requires a score of 70 or higher on the published scale - not 70 raw questions correct out of 75.
- Continental Testing Services (CTS) administers the exam for IDFPR profession 115 after CORE approval.
Exam Structure Overview
Before diving into content, it helps to understand exactly how the Illinois Department of Financial and Professional Regulation (IDFPR), Division of Professional Regulation, structures the standalone Private Detective examination (profession 115). Continental Testing Services (CTS) delivers 75 single-best-answer multiple-choice questions in a 90-minute window. There is no essay component, no practical demonstration, and no separate skills station - every question is scored the same way, and the published passing score is 70 or higher on the scale CTS reports, which is not the same as answering 70 of 75 questions correctly.
The exam is organized into three official sections, and each carries a fixed number of questions:
| Domain | Question Count | Share of Exam |
|---|---|---|
| Domain 1: Federal & State Law | 23 | ~31% |
| Domain 2: Licensing & Practice Requirements | 12 | ~16% |
| Domain 3: Detective Practices | 40 | ~53% |
If you want the full mechanics of what "passing" actually means on this scale, see IL-PD Passing Score 2026: Exactly What You Need to Pass. For a broader look at difficulty across all three domains together, How Hard Is the IL-PD Exam? Complete Difficulty Guide 2026 is worth reading before you build a study plan.
Domain 1: Federal & State Law (23 Questions)
Federal & State Law is the second-largest domain and the one where candidates most often underestimate the reading load. With 23 of 75 questions, roughly three out of every ten questions on your exam will come from this area. Because Illinois private detective practice sits at the intersection of criminal procedure, civil liability, and regulatory statute, this domain tends to test comprehension and application rather than rote memorization.
Domain 1: Federal & State Law
Candidates must be able to identify which laws govern investigative conduct, evidence handling, and the legal boundaries of surveillance and information-gathering activity in Illinois.
- Illinois statutes governing private detective licensure and permissible conduct
- Constitutional limits on searches, surveillance, and information collection
- Privacy law as it applies to records access and third-party information
- Legal consequences of exceeding investigative authority
- Interaction between state licensing law and federal restrictions relevant to investigative work
Because this domain draws from statutory language, it rewards candidates who read source material carefully rather than skim summaries. A single misread qualifier - "may" versus "shall," or a jurisdictional limitation - can flip the correct answer on a scenario-based question. This is one of the reasons a structured IL-PD Study Guide 2026: How to Pass on Your First Attempt approach that isolates statute review from practice-based review tends to outperform generalized cramming.
Domain 2: Licensing & Practice Requirements (12 Questions)
Domain 2 is the smallest section at 12 questions, but its content overlaps heavily with the administrative requirements you'll already be navigating just to sit for the exam - which makes it one of the more efficient domains to prepare for.
Domain 2: Licensing & Practice Requirements
This domain tests knowledge of the regulatory framework that governs who can hold a license, how licenses are maintained, and what practice boundaries apply once licensed.
- Eligibility criteria, including the age-21 minimum and qualifying experience documentation
- How education credit applies - an approved bachelor's degree credits two years, an associate degree one year, with a separate route for qualifying military law-enforcement training
- Required insurance coverage and its relationship to license issuance
- License renewal cycle and continuing training obligations
- Distinctions between individual licensing, agency licensing, and employee PERC registration
Because this domain mirrors the actual paperwork you file with IDFPR CORE, reviewing your own application materials doubles as exam prep. If you haven't yet mapped out your eligibility path, IL-PD Requirements 2026: Eligibility, Prerequisites & How to Qualify walks through the experience, education, and background documentation in detail - and reading it before you study Domain 2 will make the content far less abstract.
Key Takeaway
Domain 2 questions often test the same numbers you'll use on your license application - insurance minimums, renewal cycles, and training-hour requirements. Study your paperwork and the domain content together.
Domain 3: Detective Practices (40 Questions)
Detective Practices is the exam's center of gravity. At 40 of 75 questions, it accounts for more than half the test, which means your overall score depends more on this domain than on the other two combined. Unlike Domains 1 and 2, which are largely law- and administration-based, Detective Practices tests applied field judgment: what a licensed investigator does, in what order, and how the work is documented.
Employers hiring licensed private detectives in Illinois - insurance defense firms, corporate risk departments, law offices, and independent agencies - expect this domain's content to already be second nature, since it reflects daily fieldwork rather than exam trivia. If you're weighing whether the credential fits your career path, IL-PD Jobs and IL-PD Salary Guide 2026: Complete Earnings Analysis give useful context on where this domain's skills get applied on the job.
Inside the Detective Practices Subareas
Detective Practices is not tested as one undifferentiated block. The published allocation breaks it into three subareas - these are subareas within Domain 3, not additional top-level domains, but they matter for how you allocate study time.
Gathering Information (16 Questions)
Covers the methods and legal boundaries of collecting facts, records, and observational evidence during an active investigation.
- Interview and interrogation technique fundamentals
- Surveillance methodology and its documentation
- Records and background-check sourcing
- Chain-of-custody handling for physical and digital evidence
Case Management (12 Questions)
Covers how an investigation is planned, tracked, and closed out from intake through resolution.
- Case intake, scoping, and client communication
- Time and resource allocation across an active caseload
- Coordination with attorneys, insurers, or law enforcement where applicable
- Case closure and file retention standards
Analysis, Reporting & Presentation (12 Questions)
Covers turning raw findings into a defensible, well-organized work product.
- Analyzing gathered evidence for relevance and reliability
- Report structure and factual accuracy standards
- Presenting findings to clients, attorneys, or courts
- Distinguishing observation from inference in written reports
Notice that Gathering Information alone (16 questions) outweighs either of the other two subareas individually, and roughly matches Domain 2 in total size. That's a useful benchmark: if your practice tests show weakness specifically in gathering-information scenarios, that single subarea deserves more remediation time than an entire pass through Licensing & Practice Requirements.
How Domain Weighting Should Drive Your Registration Timeline
Domain weighting isn't just a study-planning detail - it interacts directly with how much runway you need before your test date. Because Detective Practices requires applied judgment rather than memorized statute, most candidates need more repetition-based practice for that domain, which argues for registering early rather than waiting until the last eligible window.
The registration sequence itself is fixed: apply to IDFPR CORE first, receive Department approval, and only then register with CTS using your authority-to-sit/examination approval ID. Department approval must precede CTS registration - there is no way to shortcut this order. The current CTS schedule lists an October 28, 2026 sitting in Hillside, with an October 7 CTS registration deadline, so your CORE approval needs to land well before that cutoff. Full scheduling detail, including how the approval-then-register sequence plays out in practice, is covered in IL-PD Exam Dates 2026: Testing Windows, Deadlines & Scheduling.
Retesting remains subject to valid qualifications and application status, meaning a failed attempt doesn't just cost the exam fee again - it also requires your eligibility documentation to still be current. That's another reason to treat Domain 3 preparation as the priority rather than an afterthought: it's the domain most likely to determine a retake.
A Domain-Ordered Study Schedule
Generic weekly templates rarely map well onto a domain structure this uneven - 40 questions in one section and 12 in another calls for uneven time allocation, not equal weeks per topic. Here is a schedule ordered by domain weight rather than by calendar convenience.
Detective Practices Foundations
- Work through Gathering Information subarea material first - it's the single largest subarea
- Build a rotating set of interview, surveillance, and evidence-handling scenarios
Case Management and Reporting
- Move into Case Management and Analysis/Reporting subareas
- Practice converting raw findings into report-style answers, since this domain tests applied judgment, not recall
Federal & State Law
- Read statute sections closely rather than relying on paraphrased summaries
- Focus on scenario questions that test legal boundaries, not just definitions
Licensing & Practice Requirements + Full Review
- Cross-check this domain against your own CORE application details
- Run full-length, 75-question timed practice sets to simulate the 90-minute limit
Notice the schedule spends roughly two-thirds of its weeks on Domain 3 content, matching its two-thirds-plus share of the exam. For a condensed, last-week reference once you've completed this cycle, keep the IL-PD Cheat Sheet 2026: One-Page Review of Must-Know Facts on hand, and run full practice sets through the practice test platform to get comfortable with the 90-minute pacing before test day.
Key Takeaway
Allocate study time proportionally to question count: Detective Practices deserves roughly half your prep hours, not an equal one-third split with the other two domains.
FAQ: IL-PD Exam Domains
There are three official sections: Federal & State Law (23 questions), Licensing & Practice Requirements (12 questions), and Detective Practices (40 questions), totaling 75 questions.
Gathering Information (16), Case Management (12), and Analysis, Reporting & Presentation (12) are subareas within the single Detective Practices domain, not separate top-level domains with independent pass requirements.
Since Detective Practices makes up more than half the exam's 75 questions, most candidates benefit from starting there, then moving to Federal & State Law, and finishing with Licensing & Practice Requirements.
No. That separately qualified sitting uses 115 questions and a 120-minute limit with its own application and fees, distinct from the standalone 75-question, 90-minute Private Detective exam covered here.
The published passing score is an overall score of 70 or higher rather than a per-domain cutoff, though weak performance in the 40-question Detective Practices domain will heavily influence that overall result. See IL-PD Pass Rate 2026: What the Data Shows for more context.