This guide is maintained as a current resource for July 2026 and covers only the laws of England and Wales. Information is for general guidance, not legal advice. Consult a qualified solicitor for advice specific to your situation.
Comprehensive guide for employers in England and Wales on investigating workplace discrimination complaints, explaining legal responsibilities under the Equality Act 2010, step‑by‑step investigation procedures, evidence gathering, tribunal implications, and best practice for fair, lawful outcomes.
Workplace discrimination complaints are a significant legal and operational issue for employers in England and Wales. When an employee or worker alleges discrimination, the employer must assess and investigate the complaint in a way that is fair, lawful, and proportionate. Discrimination law in the UK is primarily governed by the Equality Act 2010, which protects individuals from unfavourable treatment on the basis of protected characteristics such as age, race, sex, disability, religion or belief, sexual orientation, gender reassignment, marriage and civil partnership, and pregnancy and maternity. Failing to investigate discrimination complaints properly can lead to formal grievances, claims to an employment tribunal, compensation awards, legal costs, reputational harm, and regulatory scrutiny.
This article explains how employers should respond to discrimination complaints, the legal expectations for investigations, practical steps for handling them, and how the process interfaces with employment law and tribunals.
Understanding Discrimination and Employer Responsibilities
What Is Discrimination?
Under the Equality Act 2010, discrimination arises when someone is treated less favourably because of a protected characteristic. Forms of discrimination include:
- Direct discrimination – less favourable treatment directly because of a protected characteristic.
- Indirect discrimination – a policy or practice that applies to everyone but disadvantages a particular group.
- Harassment – unwanted conduct related to a protected characteristic that violates someone's dignity.
- Victimisation – unfavourable treatment because someone has made or supported a discrimination complaint.
Employers are legally liable not only for their own discriminatory acts but also for discriminatory acts carried out by employees in the course of their employment unless they can show they took all reasonable steps to prevent it.
Employer Duty to Investigate
When a discrimination complaint is raised, employers have a legal and ethical duty to investigate. This duty arises both from general employment law and from good practice principles established by bodies such as the Advisory, Conciliation and Arbitration Service (Acas). A failure to investigate, or to do so fairly and promptly, can aggravate tribunal claims and may lead tribunals to view an employer's conduct as unreasonable.
Step-by-Step Guide to the Investigation Process
1. Receiving a Complaint
An employee may bring a complaint informally, formally, or through a representative such as a trade union official. As an employer:
- Acknowledge receipt promptly and respond without undue delay.
- Discuss how the complainant would prefer the issue to be handled (informal vs formal) but retain discretion to determine the appropriate route, especially if serious issues are raised.
- Treat all complaints seriously and confidentially.
2. Deciding to Investigate
The employer must decide quickly whether to start an investigation. For formal or serious allegations, a formal investigation is usually appropriate. An investigation is also advisable when informal resolution is unlikely to address the complaint. Starting early helps ensure evidence is fresh and the process is perceived as fair.
3. Preparing the Investigation
Preparation should include:
- Appointing an investigator who is impartial and has no direct involvement in the case. When possible, choose someone trained in workplace investigations.
- Setting terms of reference that define the scope of the investigation, including what aspects of the complaint will be examined.
- Explaining the process to all parties, including the expected timeline and procedural rights (for example, the right to be accompanied in formal meetings).
- Ensuring procedural fairness, consistent with the Acas Code of Practice on disciplinary and grievance procedures. Tribunals will assess whether the procedure was reasonable and fair.
4. Gathering Evidence
The investigator should:
- Interview the complainant to understand the nature of the allegations.
- Interview the respondent (the person subject to the complaint) to hear their account.
- Speak to witnesses who may have observed relevant behaviour.
- Review documents, emails, and records related to the complaint.
- Keep detailed notes of all meetings and evidence collected.
Evidence should be documented clearly and objectively to support findings and conclusions. Detailed records are crucial if the matter progresses to an employment tribunal.
5. Witness and Parties' Meetings
Meetings should be conducted in a structured manner:
- Give reasonable notice of meetings.
- Allow the individual being interviewed to be accompanied by a colleague or trade union representative where appropriate.
- Maintain an open mind and avoid assumptions.
6. Conclusion and Report
After completing interviews and reviewing evidence:
- Prepare a written report that summarises the investigation, outlines findings, and explains the rationale for conclusions.
- Recommend actions if discrimination is found, which may include remedial steps, disciplinary action, adjustments to policies, or training.
- If no discrimination is found, document why and ensure the determination is supported by the evidence.
7. Post-Investigation Steps
After concluding the investigation:
- Inform the complainant and respondent of the outcome in writing.
- Advise both parties of any actions to be taken and relevant internal appeal rights.
- Take steps to prevent retaliation or victimisation against the complainant or witnesses.
- Review and update policies and training based on what has been learned.
Legal Risks and Tribunal Considerations
Tribunals expect employers to follow fair processes. If an employer fails to investigate a complaint properly or appears to dismiss it without reasonable inquiry, that failure can aggravate a discrimination claim and increase the likelihood of compensation and other remedies being awarded. Tribunals may also consider an employer's conduct when assessing remedies such as uplifts in awards for failure to comply with procedural standards.
An employer should also be mindful of victimisation claims, which can arise if an employee is treated unfavourably for raising a complaint. Actions perceived as retaliatory - such as sidelining the complainant after investigation - risk further claims.
Practical Examples
Example 1: A Black employee alleges repeated racial remarks by a supervisor. The employer appoints an impartial HR manager to investigate, interviews relevant people, reviews internal communications, and finds evidence of inappropriate conduct. The employer takes corrective action, including training, and updates its discrimination policy.
Example 2: A worker reports gender discrimination in promotion decisions. The employer fails to investigate and dismisses the concern. The worker brings a tribunal claim. The tribunal considers the lack of investigation a procedural failing that undermined trust in the employer's processes, potentially leading to a higher compensation award.
Common Questions
Do employers need to involve solicitors?
Employers are not required to involve solicitors in every internal discrimination investigation, but legal advice can be valuable for complex cases or where there is a risk of tribunal claims.
Can investigations be informal?
Yes, minor matters might be resolved informally, but serious allegations of discrimination generally require a formal, documented investigation.
What if the complaint is historical?
Employers should still take it seriously. While evidence may fade over time, dismissing a complaint outright because of delay can itself be unreasonable in certain circumstances.
Final Thoughts
Investigating discrimination complaints is a core responsibility for employers in England and Wales. A well-managed process not only fulfils legal obligations under the Equality Act 2010 but also supports a respectful and inclusive workplace. Employers should act promptly, investigate fairly and thoroughly, document every step, and communicate outcomes transparently. Effective handling of discrimination complaints can reduce legal risk, improve workplace culture, and ensure compliance with employment law and good practice standards.
