Employment Rights Act 1996: Primary legislation establishing fundamental employment rights, unfair dismissal provisions, and requirements for disciplinary procedures. Forms the backbone of employment law in England and Wales.

ACAS Code of Practice: Statutory code providing guidance on fair disciplinary processes. While not law itself, tribunals consider compliance with this code when making decisions, and failure to follow can result in increased compensation awards.

Equality Act 2010: Legislation ensuring warning letters and disciplinary processes are not discriminatory based on protected characteristics. Requires reasonable adjustments for disabled employees and protects against victimization.

Human Rights Act 1998: Ensures fundamental rights in disciplinary processes including right to fair treatment, privacy, and representation. Must be considered when drafting warning letters.

Data Protection Act 2018 and UK GDPR: Governs the handling of personal data, record keeping requirements, and employee's right to access records in disciplinary processes. Essential for documentation and storage of warning letters.

Company Policies and Procedures: Internal disciplinary procedures and policies that must be aligned with the warning letter. Ensures consistency with employment contract terms and company standards.