How to avoid unfair dismissal pitfalls
Ensuring a safe and productive workplace is a fundamental responsibility for employers, sitting alongside statutory duties under the Health and Safety at Work etc. Act 1974.
For many organisations, this includes a Drugs and Alcohol Policy supported by workplace testing. When carried out correctly, testing protects employees and reduces risk. However, when done hastily, employers expose themselves to significant legal risk.
At Forensic Resources Ltd (FRL), we frequently assist HR professionals and employment lawyers in navigating this delicate area. The biggest challenge? A misunderstanding of what tests actually prove — and when it is legally safe to act.
Point of Care Testing (POCT): Useful, but presumptive only
Many employers favour Point of Care Tests (POCTs) — quick, onsite screening tests (saliva or urine) that give an immediate indication of substance presence.
The benefits of POCT:
- Speed: Immediate results.
- Cost-Effective: Relatively inexpensive.
- Risk Management: Supports immediate decisions, such as temporarily removing an employee from a safety-critical role.
The critical limitation:
POCT results are presumptive only. This is a position recognised within UK forensic toxicology standards. They cannot confirm:
- If the reading is analytically accurate.
- If the substance is an illicit drug or a lawful prescription medication.
- If “cross-reactivity” has produced a false positive.
Crucial Distinction: At this stage, results should be described as “non-negative,” not “positive.” No employee should ever be dismissed based solely on a POCT result.
Why laboratory confirmation is essential
A non-negative POCT result is only the first step. Employers must send the sample to an accredited forensic toxicology laboratory for confirmatory analysis.
In the UK, laboratories should be accredited by UKAS to ISO/IEC 17025, the recognised standard for testing competence. Confirmatory analysis uses validated techniques like Gas Chromatography–Mass Spectrometry (GC-MS) to:
- Identify the exact drug or metabolite present.
- Quantify the levels detected.
- Eliminate false positives.
- Produce results suitable for disciplinary and tribunal proceedings.
Skipping this stage undermines procedural fairness and leaves the employer legally vulnerable.
The “medication” factor: understanding context
A confirmed finding does not automatically indicate misconduct. Employers must consider if the drug detected is a metabolite of lawful medication.
- The Codeine Example: Codeine is a lawful medication that metabolises into morphine. A morphine finding may reflect legitimate codeine use rather than illicit opioid consumption.
- Other Triggers: Antidepressants, ADHD medications, and sleep aids can legitimately influence toxicology results.
If HR teams do not understand the results, they should seek a formal toxicology report or pharmacological opinion to determine whether the findings indicate impairment rather than mere presence.
A fair and defensible process: 7 steps for employers
To minimise risk and ensure a fair investigation under UK employment law, follow this structured approach:
- Maintain a Clear Policy: Reflect HSE and GOV.UK guidance regarding consent and proportionality.
- Use Accredited Laboratories: Ensure results are scientifically and legally defensible.
- Ensure Chain of Custody: Maintain sample integrity from collection to reporting.
- Wait for Confirmation: Never discipline based on POCT results alone.
- Seek Expert Interpretation: Understand why a result occurred.
- Consider Mitigation: Evaluate medical explanations as part of a fair investigation.
- Document Everything: Build a strong evidence trail for potential tribunals.
Why being “test-ready” matters
Workplace drug testing is time-critical. Drugs remain detectable for a finite period; delays in sample collection can result in the permanent loss of evidence.
Furthermore, delays have cost implications, such as prolonged suspension on full pay. Being pre-registered with a laboratory provider allows for same-day sample collection and fast-track results.
About Forensic Resources Ltd (FRL)
A premier forensic science consultancy firm, FRL specialises in providing expert witness services to legal teams and insurance firms. If you’re implementing or reviewing a drug testing process — or if you have a live case requiring expert input — we’re here to help with clear, scientifically robust guidance every step of the way.
Abi Carter
Forensic Resources Ltd
Key takeaways for HR professionals (FAQs)
Can I dismiss an employee based on an onsite “Instant” test?
No. HSE guidance and UK employment law principles require laboratory confirmation (GC-MS/LC-MS) before drawing conclusions of misconduct.
What is the difference between “Non-Negative” and “Positive”?
A “non-negative” is an unconfirmed screening result. A “positive” is a legally defensible result confirmed by a UKAS-accredited laboratory.
Does a positive result always mean impairment?
Not necessarily. Interpretation by a toxicologist is required to differentiate between illicit use, historical use, and lawful prescription medication.
CONTACT US
We’re here to help with any questions or concerns you may have. Whether you need expert advice or would like an initial conversation about our services, pricing, or the options available, please don’t hesitate to get in touch. At Refreshing Law, what sets us apart from other law firms is that you’ll get to speak to an experienced employment lawyer right from the very first call.
lreynolds@refreshinglawltd.co.uk
Lousha Reynolds
Refreshing Law