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The short version
If you see something illegal, dangerous, or seriously wrong on a construction site and you report it, the law protects you from being punished for speaking up. That protection comes from the Public Interest Disclosure Act 1998, which sits inside the Employment Rights Act 1996. You don't need two years' service. You don't need to be an employee -- workers, agency workers, trainees, and LLP members are covered too. If you're dismissed for whistleblowing, that's automatically unfair -- no qualifying period, no cap on compensation. But the disclosure has to meet specific legal tests. Getting those right is the difference between being protected and being exposed.
Why this matters in construction
Construction sites are where things go wrong in ways that can kill people. Unsafe scaffolding. Missing edge protection. Asbestos not reported. Falsified inspection records. Workers without CSCS cards operating plant. Subcontractors paid cash to avoid tax. Corners cut on fire stopping. CDM documentation that doesn't exist.
The people who see this first are the people on site -- operatives, supervisors, site managers. And the people who report it are routinely punished for it. Not called back. Moved to a worse site. Labelled a troublemaker. Told their contract's "finished."
The blacklisting scandal (see guide 3.9) proved that construction companies systematically targeted workers who raised health and safety concerns. The law exists specifically to stop that happening.
What counts as a protected disclosure
A qualifying disclosure is a disclosure of information that, in the reasonable belief of the worker, is made in the public interest and tends to show one or more of the following:
| Category | Construction examples |
|---|---|
| (a) A criminal offence has been, is being, or is likely to be committed | Fraud on contract pricing, theft of materials, assault on site, employing illegal workers |
| (b) A person has failed, is failing, or is likely to fail to comply with a legal obligation | Breaching CDM Regulations, failing to report RIDDOR incidents, not paying minimum wage, CIS fraud, breaching planning conditions |
| (c) A miscarriage of justice has occurred, is occurring, or is likely to occur | Falsely blaming a worker for an incident they didn't cause |
| (d) The health or safety of any individual has been, is being, or is likely to be endangered | Unsafe working at height, missing guard rails, defective plant, inadequate welfare, asbestos exposure, overloaded scaffolding |
| (e) The environment has been, is being, or is likely to be damaged | Illegal waste disposal, contaminated land not reported, pollution of watercourses from site run-off |
| (f) Information about any of the above has been, is being, or is likely to be deliberately concealed | Covering up an accident, destroying inspection records, hiding a near-miss report |
Key legal tests
For a disclosure to be protected, it must satisfy all of the following:
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It must be a disclosure of information -- not just a vague allegation. "The scaffolding is unsafe" is weaker than "the scaffolding on Block C was erected on Monday without base plates, and the scaffold inspection tag hasn't been signed since the 15th." Facts and specifics matter.
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The worker must have a reasonable belief that the information tends to show one of the six categories. They don't have to be right -- the belief just has to be reasonable.
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The worker must reasonably believe the disclosure is made in the public interest. A purely personal grievance (e.g. "my pay is wrong") is unlikely to qualify -- unless it affects others too (e.g. "nobody on this site is being paid minimum wage").
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It must be made to an appropriate person -- the route matters (see below).
Who can blow the whistle
| Covered | Not currently covered |
|---|---|
| Employees | Genuinely self-employed individuals |
| Workers (including casual/zero-hours) | Volunteers |
| Agency workers | Trustees |
| Trainees | Non-executive directors (in most cases) |
| LLP members | |
| NHS practitioners, police officers |
Construction trap: If someone is labelled "self-employed" but is actually a worker or employee (see guides 3.1--3.8), they're covered by whistleblowing protection. The label doesn't determine it -- the reality of the working relationship does.
If you're genuinely self-employed, you're not currently protected under PIDA. But you may still be able to report concerns to regulators (HSE, Environment Agency, HMRC) without the employment protection framework.
Who to disclose to -- and why it matters
The level of protection depends on who you tell:
Tier 1: Disclosure to your employer (s.43C)
| Test | Detail |
|---|---|
| To whom | Your employer, or another person the employer has authorised to receive disclosures |
| Protection test | Lowest threshold -- just needs to be a qualifying disclosure made in good faith |
| Construction reality | Tell your site manager, your contracts manager, or use the company's whistleblowing procedure if there is one |
This is the safest and most protected route. Always try this first unless there's a good reason not to.
Tier 2: Disclosure to a prescribed person (s.43F)
| Test | Detail |
|---|---|
| To whom | A person or body on the government's prescribed persons list |
| Protection test | Worker must reasonably believe the information and the allegation are substantially true |
| Key prescribed persons for construction | HSE (health and safety), Environment Agency (environmental damage), HMRC (tax fraud, CIS abuse), Local authority (planning/building control), Gangmasters and Labour Abuse Authority (labour exploitation) |
Use this route if your employer ignores the concern, if you believe the employer is involved in the wrongdoing, or if you'd face retaliation for reporting internally.
Tier 3: Wider disclosure (s.43G)
| Test | Detail |
|---|---|
| To whom | Anyone -- including the media, MPs, clients |
| Protection test | Highest threshold. Must meet all of: (a) reasonable belief in truth; (b) not made for personal gain; (c) reasonable in all circumstances; plus at least one of: reasonably believed employer would subject them to detriment, no prescribed person and reasonably believed evidence would be concealed/destroyed, or previously disclosed to employer/prescribed person |
| Construction reality | Going to the press or to a client about safety failures. Only do this as a last resort -- the legal tests are much harder to satisfy |
Disclosure to a legal adviser (s.43D)
Always protected if made in the course of obtaining legal advice. No additional tests.
What protection looks like
Protection from detriment (s.47B ERA 1996)
A worker has the right not to be subjected to any detriment by their employer on the ground that they have made a protected disclosure.
Detriment includes:
- Not being called back for shifts
- Being moved to a worse site or role
- Being excluded from overtime or bonuses
- Disciplinary action
- Bullying, hostility, or isolation
- Being given unsafe or unpleasant work as punishment
- Being "managed out"
- Being blacklisted (see guide 3.9)
Protection from dismissal (s.103A ERA 1996)
If the reason (or principal reason) for dismissal is that the worker made a protected disclosure, the dismissal is automatically unfair.
| Feature | Detail |
|---|---|
| Qualifying period | None -- day-one right |
| Compensation cap | None -- uncapped, based on actual loss |
| Interim relief | Available -- worker can apply within 7 days of dismissal for an order to continue employment pending the full hearing |
What's changing -- ERA 2025
| Change | When | What it means |
|---|---|---|
| Sexual harassment = qualifying disclosure | 6 April 2026 | Disclosures about sexual harassment explicitly qualify as protected disclosures under s.43B. Workers who report sexual harassment are entitled to full whistleblowing protection -- no detriment, automatically unfair dismissal if sacked |
| NDAs cannot silence harassment disclosures | Coming (date TBC) | Non-disclosure agreements that seek to prevent disclosures about harassment or discrimination will be void |
Construction impact: From April 2026, if someone on site reports sexual harassment -- to their employer, to a prescribed person, or through a whistleblowing channel -- they have explicit whistleblowing protection. Dismissing or penalising them is automatically unfair, uncapped compensation. This aligns with the broader ERA 2025 changes on employer liability for third-party harassment coming in October 2026 (see guide 3.13).
Whistleblowing on construction sites -- real scenarios
Scenario 1: Unsafe scaffolding
You notice the scaffolding on Block B hasn't been inspected in over a week. The inspection tag is missing. You raise it with the site manager. They tell you to "stop causing problems" and the next week you're told your contract's finished.
Protected? Almost certainly. Health and safety of individuals endangered (category d). Disclosure made to employer (Tier 1). Dismissal likely automatically unfair.
Scenario 2: Falsified RAMS
You discover the risk assessments and method statements for the demolition work are copy-pasted from a different project and don't reflect the actual conditions. You report it to the principal contractor's project manager. Nothing happens. You report it to the HSE.
Protected? Yes. Failure to comply with legal obligations (category b -- CDM Regulations). Disclosure to employer first (Tier 1), then to a prescribed person (Tier 2 -- HSE). Both protected.
Scenario 3: CIS fraud
You realise the contractor is paying workers cash in hand without making CIS deductions or reporting to HMRC. You report it to HMRC.
Protected? Yes -- provided you reasonably believe a criminal offence or breach of legal obligation is occurring (categories a and b), and you reasonably believe the information is substantially true (Tier 2 test for prescribed persons).
Scenario 4: The Balfour Beatty case
An employee discovered that Balfour Beatty had concealed true profit margins on a Welsh Government contract, inflating them from 3.3% to 7.34% by not submitting the lowest subcontractor quotes. He raised it internally -- and was met with bullying, denial, and exclusion. He resigned and won £137,000 in a constructive dismissal/whistleblowing claim.
What happens if you get it wrong -- as an employer
| Consequence | Detail |
|---|---|
| Automatically unfair dismissal | No qualifying period, no cap on compensation. Awards regularly reach six figures |
| Detriment claims | Compensation for financial loss and injury to feelings |
| Vicarious liability | The employer is liable for acts of managers and co-workers who subject the whistleblower to detriment |
| Personal liability | Individual managers can be personally liable for subjecting a whistleblower to detriment |
| Regulatory consequences | If the whistleblower goes to the HSE or Environment Agency, expect an investigation -- not just of the original concern, but of why it wasn't dealt with internally |
| Reputational damage | Tribunal judgments are public. Being found to have punished a whistleblower is devastating for a contractor's reputation, especially on public-sector work |
| Interim relief | If granted, the employer may be ordered to continue paying the whistleblower's wages and benefits pending the full hearing -- which could be months away |
What to do
If you see something wrong on site:
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Write it down. Date, time, location, what you saw, who was involved. Be specific -- facts and information, not just opinions.
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Report internally first (where safe to do so). Use the company's whistleblowing procedure if there is one. Put it in writing -- email, letter, text. Keep a copy.
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If your employer ignores it, or you believe they're complicit, report to a prescribed person:
- Health and safety: HSE -- hse.gov.uk or 0300 003 1647
- Environmental: Environment Agency -- 0800 80 70 60
- Tax/CIS fraud: HMRC
- Labour exploitation: Gangmasters and Labour Abuse Authority (GLAA)
- Building safety: Local authority building control, or the Building Safety Regulator
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Don't stay silent because you're worried about your job. The whole point of the law is to protect you. But make sure your disclosure meets the legal tests -- information, reasonable belief, public interest.
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Get legal advice early. Protect (the whistleblowing charity) offers free, confidential advice: 020 3117 2520 or protect-advice.org.uk. If you're in a union, contact them immediately.
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If you're dismissed or penalised, you have 3 months minus one day to file a tribunal claim. For interim relief, you must apply within 7 days of dismissal. Don't delay.
If you're an employer:
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Have a whistleblowing policy. Written, accessible, communicated at induction. It must explain what a protected disclosure is, how to report, and that retaliation won't be tolerated.
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From April 2026, update it to include sexual harassment as a qualifying disclosure.
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Investigate concerns properly. Take them seriously. Respond in writing. Keep records of what you did and why.
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Don't punish the messenger. No dismissal, no detriment, no "managing out," no blacklisting. Train your managers to understand this.
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The cost of getting this wrong is uncapped. A whistleblowing dismissal claim with no compensation cap, combined with regulatory scrutiny and reputational damage, can be existential for a small contractor.
What to do next
- Write down exactly what you saw: date, time, location, what happened, who was involved. Be specific with facts, not opinions.
- Report internally first where safe to do so -- use the company's whistleblowing procedure if there is one, and put it in writing.
- If your employer ignores it or is involved, report to the relevant prescribed person (HSE, Environment Agency, HMRC, or GLAA).
- Contact Protect (the whistleblowing charity) for free, confidential advice before making a disclosure.
- If you're dismissed or penalised, act fast -- you have three months minus one day for a tribunal claim, and only seven days for interim relief.
Sources
- Employment Rights Act 1996, ss.43A--43L (as inserted by the Public Interest Disclosure Act 1998)
- Employment Rights Act 1996, s.47B (protection from detriment)
- Employment Rights Act 1996, s.103A (automatically unfair dismissal)
- Employment Rights Act 2025 -- sexual harassment as qualifying disclosure (from 6 April 2026)
- GOV.UK -- Whistleblowing: List of Prescribed People and Bodies
- GOV.UK -- Whistleblowing: Prescribed Persons Guidance
- HSE -- Whistleblowers: Contact HSE
- HSE -- Whistleblowing and Whistleblowers: Operational Guidance
- Protect (whistleblowing charity) -- Prescribed Persons Reporting Duty
- Stephens Scown -- Employee Wins £137,000 Whistleblowing Case Against Balfour Beatty
- Harrison Drury -- Employment Rights Act 2025 Expands Whistleblowing Protection to Sexual Harassment
- Penningtons -- Harassment and the ERA 2025: What Employers Need to Know
- Safecall -- Employment Rights Act 2025 (whistleblowing provisions)
- ACAS -- Employment Rights Act 2025 (whistleblowing protections for sexual harassment)
- CIPD -- Whistleblowing: Changes under the Employment Rights Act 2025
- Shoosmiths -- 2026: A New Era for the Duty to Prevent Sexual Harassment
This guide is for general information only and does not constitute legal, tax, or financial advice. Legislation, case law, and guidance change frequently. Whistleblowing claims are fact-sensitive and depend on the specific circumstances of each disclosure. The ERA 2025 provision on sexual harassment as a qualifying disclosure commences on 6 April 2026. Always take professional advice specific to your situation before acting on anything in this guide. Protect (020 3117 2520) offers free confidential whistleblowing advice. SiteKiln is not a law firm and accepts no liability for actions taken based on this content.
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