Sergeant Exam (NPPF) vs Detective Exam (NIE): which career suits you?
Two College of Policing law exams with different purposes. The sergeants' NPPF step two exam is the promotion route: 150 questions in 3 hours across crime, evidence and procedure, and general police duties, 55% to pass. The National Investigators' Exam (NIE) is for trainee investigators entering detective work on the PIP2 pathway: 80 questions in 2 hours on general principles and police powers, serious crime, property offences and sexual offences, scored on 70 questions with a 55.7% pass mark (39 of 70). Pick the NIE if you want to become a detective; the sergeants' exam if you want to lead a team.
Sergeant Exam (NPPF) vs Detective Exam (NIE) at a glance
| Sergeant Exam (NPPF) | Detective Exam (NIE) | |
|---|---|---|
| Full name | Police Sergeant Promotion: NPPF Step Two Legal Exam | Detective Constable: National Investigators' Exam (NIE) |
| Questions | 150 multiple-choice questions; 10 poorly performing questions are removed at marking, so you are scored on 140 | 80 multiple-choice questions; 10 poorly performing questions are removed at marking, so you are scored on 70 |
| Time | 3 hours | 2 hours |
| Passing score | 55% (77 of the 140 scored questions). 75% or more earns an exceptional grade; under 30% is a low-band fail | 55.7% (39 of the 70 scored questions). 85.7% or more earns an exceptional grade |
| Format | Syllabus is only the 2027 edition of the Blackstone's Police Manuals (Crime; Evidence and Procedure; General Police Duties, which now contains road policing). No help from anyone else, no AI tools and no unauthorised devices; breaches go to the College's disqualification panel. Questions test application, not recall of tables | Syllabus is only the Blackstone's Police Investigators' Manual for the exam year (2027 edition for 2027 sittings), in four areas: general principles, police powers and procedures; serious crime and other offences; property offences; sexual offences. The College recommends at least 14 weeks of independent study. No help from others, no AI tools, no unauthorised devices |
| Cost | No candidate exam fee is published by the College; entry is arranged through your force. Officers and staff in England and Wales get 30% off the Blackstone's manuals | No candidate exam fee is published by the College; entry is arranged through your force or organisation |
| Languages | English | English |
| Where | Online, unsupervised, on your own device at home or in a force testing room; registration through your force examinations officer on the College's AIMS system. 2027 sittings: 16-18 March and 5-7 October (any day in the window, 8am to 8pm) | Online, unsupervised, on your own device or in a force testing room; register through your NIE liaison contact on the College's AIMS system. 2027 dates: 2 March, 8 June, 7 September and 16 November (8am to 8pm) |
| Level | Police | Police |
What each exam covers
Sergeant Exam (NPPF)
- Promotion Process, Eligibility and the Exam
- Crime
- Evidence and Procedure
- Custody, Detention and Interviews (PACE Codes C to F)
- General Police Duties
- Road Policing
- NPPF Steps Three and Four: Assessment and Interview
- Study Plan and Exam Technique
Detective Exam (NIE)
- The Trainee Investigator Route, PIP2 and the NIE
- General Principles, Police Powers and Procedures
- Serious Crime and Other Offences
- Property Offences
- Sexual Offences
- Investigation Practice: Interviews, Disclosure and Covert Powers
- Detective Selection Interview and Development Programme
- Study Plan and Timeline
Which should you take?
Two College of Policing law exams with different purposes. The sergeants' NPPF step two exam is the promotion route: 150 questions in 3 hours across crime, evidence and procedure, and general police duties, 55% to pass. The National Investigators' Exam (NIE) is for trainee investigators entering detective work on the PIP2 pathway: 80 questions in 2 hours on general principles and police powers, serious crime, property offences and sexual offences, scored on 70 questions with a 55.7% pass mark (39 of 70). Pick the NIE if you want to become a detective; the sergeants' exam if you want to lead a team.
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FAQ
What is the difference between Sergeant Exam (NPPF) and Detective Exam (NIE)?
Two College of Policing law exams with different purposes. The sergeants' NPPF step two exam is the promotion route: 150 questions in 3 hours across crime, evidence and procedure, and general police duties, 55% to pass. The National Investigators' Exam (NIE) is for trainee investigators entering detective work on the PIP2 pathway: 80 questions in 2 hours on general principles and police powers, serious crime, property offences and sexual offences, scored on 70 questions with a 55.7% pass mark (39 of 70). Pick the NIE if you want to become a detective; the sergeants' exam if you want to lead a team.
Which is harder, Sergeant Exam (NPPF) or Detective Exam (NIE)?
Sergeant Exam (NPPF): 150 multiple-choice questions; 10 poorly performing questions are removed at marking, so you are scored on 140 in 3 hours. Detective Exam (NIE): 80 multiple-choice questions; 10 poorly performing questions are removed at marking, so you are scored on 70 in 2 hours. The longer exam covers more ground, but the harder one is the one further from your daily work. Take both free practice tests to see where you stand.
Can I hold both Sergeant Exam (NPPF) and Detective Exam (NIE)?
You can prepare for and apply to more than one, and many people do, because the judgement, verbal and numerical tests and the structured interviews overlap a lot. Each organisation runs its own process and vetting, and some roles can't be held at the same time (you can't be a serving regular police officer and a regular in the armed forces, for example), so check the eligibility rules in each job advert.
How do I prepare for Sergeant Exam (NPPF) and Detective Exam (NIE)?
Start with the free practice test for each, then study by topic. Premium is per exam (£45 a month each), so most people start with the exam they'll sit first and add the second when they're ready.
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Exam details are summarized from recruiting organisations' published information as of November 2026. Confirm with the recruiting organisation before you book. UKCivilServicePrep is an independent career-prep service, not affiliated with or endorsed by any government agency.