How to Become
a Detective
The route from uniformed constable to accredited detective constable in England and Wales: how forces select trainees, the National Investigators' Exam, the PIP2 programme and portfolio, how long it takes, and what happens if the exam goes wrong. Built from the College of Policing's PIP policy, HMICFRS and published force policies.
Independent information, not advice · Sources checked 18 October 2026 · England and Wales unless stated
Pass probation and get signed off at PIP1, then apply through your force's trainee detective route. You must pass the National Investigators' Exam (39 of 70 scored questions), complete the PIP2 investigator programme your force runs under College licence, and finish a workplace portfolio, usually within six to twelve months of the exam. Only then can you use the title of substantive detective. Whether you are selected before or after the NIE is up to your force.
The six-step pathway to PIP2
Detective constables are accredited investigators at PIP level 2, which the College of Policing's Professionalising Investigation Programme defines as "serious and complex investigations". PIP1 covers "priority and volume crime investigations", PIP3 major crime and serious and organised crime, and PIP4 the strategic management of highly complex investigations. The College's PIP programme policy (2023) sets out the career pathway to PIP2:
| Step | What the College's PIP policy says | In practice |
|---|---|---|
| 1. Selection | Undergo a selection process, "whether police constable to detective constable progression", an initial entry route or as a police staff investigator. | Your force's trainee detective or Detective Academy process. Whether you are selected before or after the NIE "is a matter of force policy". |
| 2. PIP1 competence | Demonstrate competence at PIP1. | Usually signed off during probation for officers on response or neighbourhood. |
| 3. Pass the NIE | Pass the National Investigators' Exam. | 80 questions in 2 hours, 39 of the 70 scored questions to pass (55.7%). |
| 4. PIP2 programme | Enrol on and pass the PIP2 investigator programme. | A force-delivered course licensed by the College. Names vary: ICIDP, DDP, IDP. |
| 5. Workplace assessment | Robust workplace assessment as a trainee investigator and a portfolio against the PIP2 assessment criteria. | A tutor, monthly reviews, and a portfolio usually finished in 6 to 12 months. |
| 6. Keep it | Complete annual CPD to retain accreditation. | The College says three consecutive years without CPD may mean you are deemed inactive. |
One line in the policy decides when you can call yourself a detective: "only those who have successfully completed the process will be able to use the title of substantive detective or police staff equivalent." Until then forces use titles such as trainee or, in Surrey and Sussex, "Learner" Detective Constable.
Step 1: getting selected by your force
There is no national application. HMICFRS reported in 2025 that the route to becoming a detective "isn't standardised across forces in England and Wales" and that "many forces have their own processes for considering applications for detective roles". What the College's policy does say is that trainee investigators "should be selected with the intention that they will become PIP 2 investigators", and that selecting them before the NIE "is a matter of force policy".
So you will meet one of two models:
- Select, then exam. You apply to a trainee detective scheme, are selected (usually application and interview), posted to an investigative team and entered for the next NIE. West Midlands Police works this way.
- Exam, then select. You pass the NIE first, often with force support, and then apply for trainee posts. Essex Police described this in 2020. If you go this way, watch the clock: the College says it is "not possible to extend a student's NIE validity period for operational reasons or lack of opportunities to progress their portfolio".
Expect the usual internal selection elements: line manager or detective inspector support (West Midlands asks for the authorising detective inspector on the NIE application), a written application against the role profile, and an interview, usually marked against the Competency and Values Framework. Show investigative thinking from your current role: files you built, enquiries you chased, a case where your early actions mattered.
Step 3: the National Investigators' Exam
The NIE is the College of Policing's gateway exam to PIP2 learning. The key facts, from the College's candidate handbook:
- Format: 80 multiple-choice questions in two hours, taken online. The 10 questions that perform least well are removed, so everyone is scored on 70.
- Pass mark: 39 out of 70 (55.7%). 60 or more (85.7%) is graded exceptional.
- Syllabus: the four parts of Blackstone's Police Investigators' Manual for the year of the exam.
- Validity: a pass lasts three years less one day.
- Who can sit it: warranted officers, police staff investigators and others selected as potential PIP2 students, who must be able to show current competence against PIP1.
- When: four sittings a year. The next sitting is Tuesday, 17 November 2026; registration through your force closes at 6pm on Wednesday, 21 October 2026, and forces may set an earlier internal deadline.
The NIE has its own section on PolicePay, with the syllabus, pass rates by force, revision plans and original practice questions: start at the NIE hub, then the syllabus and a revision plan.
Step 4: the PIP2 investigator programme
The PIP2 programme is a national curriculum delivered by forces under a College of Policing licence, which is why the course has different names. West Midlands Police calls its version the Detective Development Programme (DDP), which it describes as following "the national objectives and curriculum set by the CoP and with the requisite licence to deliver issued by the CoP". Surrey and Sussex call theirs the Investigator's Development Programme (IDP). Essex Police and older documents use ICIDP, the Initial Crime Investigators' Development Programme, which West Midlands lists as its programme's predecessor.
West Midlands' published structure gives a feel for the content:
- Induction: 1 day
- Module 1, conducting investigations into serious and complex crime: 4 days
- Module 2, public protection: 4 days
- Module 3, digital investigations: 2 days
- Module 4, wider investigative enquiries: 3 days
- Module 5, witness interviewing: 5 days
- Module 6, suspect interviewing: 5 days
Essex Police said in 2020 that its ICIDP course was "currently 4 weeks", with the whole programme taking about six weeks including interview training. Ask your force for its current structure.
Step 5: workplace assessment and the portfolio
After the classroom element comes the part that takes longest. The College's PIP policy says a trainee "should be allocated a tutor once they have completed the classroom component", and that trainee, tutor and supervisor "should meet monthly" to discuss the evidence needed, the trainee's access to relevant experience and their development plan. The portfolio is built up throughout and assessed against the PIP2 investigator criteria.
On timing, the College told an FOI requester in May 2025 that the portfolio "usually takes six to twelve months to complete, but candidates have up to three years to complete their portfolio before the National Investigator Exam (NIE) validity expires". West Midlands sets its own deadline: 12 months from the final DDP module.
Once accredited, you "should complete annual continuous professional development (CPD) to maintain accreditation", and "if they fail to complete CPD for three consecutive years they may be deemed to be inactive" (College FOI response, May 2025). The College also said an accredited PIP2 investigator "is deployable to any PIP 2 role subject to the essential criteria for the role".
How four forces run it
These are the published force documents we could read. They show how much the details vary, so treat them as examples, not as your force's rules.
| Force | What its published document says | Document |
|---|---|---|
| West Midlands Police | Detective Academy is "a bi-yearly process" open to constables "fully accredited at PIP1 level and signed off as competent within their probationary period". Successful applicants are automatically enrolled on the next NIE, get 40 duty hours to prepare over five months and one force-funded two-day crammer (in their own time). After the NIE: the Detective Development Programme, a one-day induction then six modules (about 23 days), and 12 months from the last module to finish the portfolio. | Investigative Accreditation Policy v1.0 (approved January 2025) |
| Essex Police | In 2020 the programme was advertised internally four times a year; officers joined the detective pathway when they passed the NIE; the ICIDP course was "currently 4 weeks"; officers had three years from passing the NIE to finish; support included study materials, a crammer and four days' protected study time. | FOI disclosure, 1 October 2020 (dated) |
| Surrey Police and Sussex Police | Trainees use the title "Learner", for example Learner Detective Constable, until accredited. PIP2 needs the NIE, the PIP2 Investigator's Development Programme (IDP), the Serious and Complex Interviewing Course and the IDP portfolio. | Detective Title Policy 1211 (2026) |
| Greater Manchester Police | Appointed 12 retired detectives as detective coaches, gives trainees a mock exam and a development plan based on it, and 40 hours of study leave (as reported by HMICFRS). | HMICFRS investigation inspection, 2025 |
How long it takes: a realistic timeline
Putting the official timings together, for an officer who has passed probation and is signed off at PIP1:
- Selection: depends on when your force opens its window. West Midlands runs its Detective Academy as "a bi-yearly process"; Essex advertised four times a year in 2020.
- NIE preparation: the College recommends at least 14 weeks of independent study. West Midlands says candidates should expect to sit the exam four to six months after its induction.
- Results: about three weeks after the sitting.
- PIP2 programme and portfolio: the College expects six to twelve months from the NIE pass.
So a year to eighteen months from applying to being accredited is a reasonable planning figure, with the NIE pass lasting three years less one day as a backstop if courses or casework are delayed.
Demand, and the support you should ask for
Forces need detectives. HMICFRS reported in 2025 that between March 2018 and March 2024, accredited PIP2 investigators rose from 20,356 to 22,832, but "the shortfall in the number of these investigators had increased from 4,353 to 9,441". Because of the difficulty recruiting investigators, "many forces used untrained officers and staff to fill vacancies".
Support varies widely. HMICFRS found some forces provided "paid study leave, free learning resources, coaching and places on crammer courses", while "other forces didn't put anything in place for applicants until they had passed the NIE at their own expense". Before you apply, ask your force:
- How many duty hours can I use to study? (West Midlands gives 40 over five months.)
- Will the force buy the Investigators' Manual or fund a crammer?
- Will I have a tutor or coach, and how often will we meet?
- Where will I be posted as a trainee, and when does the next PIP2 course run?
- Is there any detective incentive payment, and any tenure rule after accreditation?
On pay, a detective constable is on the constable scale. HMICFRS noted that Kent gives officers an annual payment as an incentive to become detectives, and a senior Essex officer said detective constables in certain roles get an extra £1,200 a year. Compare roles in our specialist role pay calculator.
If you fail the NIE or the portfolio
The College's policy says unsuccessful candidates "will have an opportunity, subject to force policy, to re-sit the examination on the next examination date". After a second fail, "line managers should hold discussions with the individual as to whether career progression into a PIP 2 investigation role is the most suitable route for them", with a development plan.
People who fail the NIE or do not demonstrate competence "should be provided with a development plan and relevant support". If they still cannot meet the requirements, "they will not be accredited at PIP 2 and should be removed from a PIP 2 role". West Midlands applies this strictly: after a second fail there is a development meeting and no further attempt "within 18 months", and after a third fail officers are "re-posted into a PIP1 investigative role".
Read more on what happens if you fail the NIE and the published NIE pass rates.
Other routes into investigation
- Direct entry detective routes recruit new officers straight into a detective programme. These are recruitment routes, not lateral moves: see direct entry detective explained and the NIE on direct entry routes.
- Police staff investigators can be trained to PIP2 too; the College's pathway includes them. See civilian investigator explained.
- Specialist investigation units such as public protection, serious and organised crime or counter terrorism usually want PIP2 accreditation first. Some posts with access to sensitive intelligence need management vetting.
How to prepare: what to do this month
Our practical guidance; your force's process comes first.
- Check your PIP1 sign-off. Make sure it is recorded. Without it you may not be eligible to sit the NIE.
- Find your force's route and dates. Ask your NIE liaison or examinations officer when the next trainee window and NIE registration close.
- Start reading now. Part 1 of the Investigators' Manual is the largest part of the paper. A first pass through it before you are selected makes the formal study period far easier.
- Build your case file examples. For the interview, collect three or four investigations you led or contributed to, with your decisions and their outcomes.
- Test yourself early. A scored mock shows which part of the syllabus needs most work, so you spend your study hours where they count.
Our original CID board questions are in specialist role interview questions and answers.
What we could not verify
- The full College of Policing PIP2 investigator role profile, which is behind the College Learn login.
- Current public pages for the constable to detective route in most forces, including the Met. We used the published West Midlands, Essex and Surrey and Sussex documents instead; the Essex document dates from 2020.
- Any national figure for detective vacancies after March 2024. The Home Office workforce statistics do not count detectives separately.
- Selection pass rates for trainee detective schemes. NIE pass rates are published and covered in our NIE section.
Frequently Asked Questions
How do I become a detective as a serving police officer?
Apply through your force's trainee detective route (names vary, such as Detective Academy). The College of Policing's PIP policy sets the steps: force selection, competence at PIP1, a pass in the National Investigators' Exam, the PIP2 investigator programme, then workplace assessment and a portfolio. Only those signed off can use the title of substantive detective.
Do you have to pass the NIE before becoming a trainee detective?
It depends on your force. The College's PIP policy says selecting people as trainee investigators before they enrol on the NIE is a matter of force policy. West Midlands Police selects first and then enrols you on the next NIE; Essex Police (in 2020) treated officers as on the detective pathway once they had passed it.
What is the NIE pass mark?
39 out of 70 (55.7%). The exam has 80 multiple-choice questions in two hours; the College removes the 10 that perform least well, so everyone is scored on 70. A pass is valid for three years less one day.
How long does it take to become a detective constable?
The College expects people to complete the full PIP2 programme within six to twelve months of passing the NIE, and says the portfolio usually takes six to twelve months, with up to three years before the NIE pass expires. Add the time to be selected and to prepare for the exam (the College recommends at least 14 weeks of study), and a year to eighteen months from application is a realistic planning figure, varying by force.
Can police staff become PIP2 investigators?
Yes. The College's PIP policy includes police staff investigators in the PIP2 pathway, and the NIE is open to police staff investigators selected for PIP2. The title for accredited staff is the police staff equivalent of substantive detective.
What happens if I fail the NIE?
You can usually resit at the next sitting, subject to force policy. After a second fail, the College's policy says line managers should discuss whether the PIP2 route is the right one and agree a development plan. West Midlands Police then allows no further attempt within 18 months and re-posts officers to a PIP1 role after a third fail.
Do detectives get paid more?
Not on the national pay scale: a detective constable is paid as a constable. HMICFRS reported in 2025 that some forces add incentives: Kent gives officers an annual payment as an incentive to become detectives, and a senior Essex officer said detective constables in certain roles get an extra £1,200 a year.
Is there a minimum time I must stay in CID after accreditation?
Not nationally. The College of Policing told an FOI requester in 2025 that it holds no information on any nationally mandated tenure or minimum retention period after PIP2 accreditation. Forces can set their own rules.
What does the PIP2 course involve?
It is delivered by forces under a College licence, so content is national but format varies. West Midlands Police's Detective Development Programme, for example, is a one-day induction then six modules: conducting serious and complex investigations, public protection, digital investigations, wider investigative enquiries, witness interviewing and suspect interviewing.
Sources and how we checked them
Every factual claim on this page was written from the sources below, read on 18 October 2026. Rules and figures change, so check the source for the date you are reading this. Where we could not confirm something from an official or independent source, the page says so rather than guessing. Spotted something out of date? See our corrections policy.
- College of Policing: PIP programme policy 2023 (PDF) : PIP levels, PIP2 career pathway, NIE validity and resits, six to twelve months, tutor and monthly reviews, title of substantive detective, removal from role (accessed 18 October 2026)
- College of Policing FOI response FOIA-2025-080 (29 May 2025, PDF) : portfolio six to twelve months, up to three years; annual CPD; inactive after three years without CPD; no national tenure; deployable to any PIP2 role (accessed 18 October 2026)
- College of Policing: National Investigators' Exam : who can sit it, format, pass mark, sittings (accessed 18 October 2026)
- College of Policing: NIE candidate handbook 2026 (PDF) : structure, pass mark, validity, recommended study time, 2026 dates (accessed 18 October 2026)
- West Midlands Police: Investigative Accreditation Policy v1.0 (PDF) : Detective Academy criteria, NIE support, DDP modules, portfolio deadline, resit and third-fail rules (accessed 18 October 2026)
- Essex Police FOI: Examination support service, NIE, sergeants and inspectors (1 October 2020) : advertised four times a year, 4-week ICIDP, three years to finish, support offered (dated) (accessed 18 October 2026)
- Surrey Police and Sussex Police: Detective Title Policy 1211 (PDF) : Learner title; components of PIP2 (accessed 18 October 2026)
- HMICFRS: An inspection into how effectively the police investigate crime (2025) : PIP2 numbers and shortfall, route not standardised, force support, GMP coaches, Kent and Essex incentives (accessed 18 October 2026)
- College of Policing: Investigation career pathway : NIE as gateway to PIP2 learning; PIP2 profile behind College Learn login (accessed 18 October 2026)
- joiningthepolice.co.uk: Common questions : most detectives specialise after probation (accessed 18 October 2026)
On this topic elsewhere
More in this guide series
Practice, fitness and pay
Disclaimer
PolicePay.co.uk is an independent guide. It is not affiliated with, endorsed by or produced by the College of Policing, the Home Office or any police force. Specialist selection is run by each force (or regional collaboration) and criteria, tenure rules, fitness standards and course lengths differ, so check your force's current advert and policy before you apply. Practice questions on this site are original PolicePay material, not real selection or exam content. Details apply to England and Wales unless stated. Details are as checked on 18 October 2026.