Strike action clearly constitutes a breach of contract. Industrial action short of a strike is less straightforward. This will commonly take the form of a refusal to perform full normal duties. Where these are expressly required by the contract, employees will clearly be in breach. However, the contractual position is less straightforward where such duties are implied into the contract rather than expressly included. In Sim v Rotherham Metropolitan Borough Council [1986] IRLR 391, the legality of pay deductions being made depended on whether covering for absent colleagues during school hours was a contractual duty. The court held in this case that the teachers were in breach of their contract. Subsequent to this case, the teacher's pay and conditions document now expressly provides that there is a duty to provide cover for absent colleagues. Other relevant case law is Cresswell and others v Board of Inland Revenue [1986] IRLR 190 and MacPherson v London Borough of Lambeth [1988] IRLR 470. In both these cases, the refusal of employees to operate new equipment was held to be a breach of their contracts. However, refusal to carry out genuinely voluntary duties will not be a breach of contract. For example, a blanket refusal to undertake voluntary overtime will not be a breach of contract. It may, however, amount to industrial action.
The contractual position regarding other forms of action, such as working to rule, 'go slows' or a general withdrawal of goodwill can also be unclear because there may appear to be no existing contractual term to be breached. However, the courts have been willing to view any intention to disrupt an employer's business as a breach of contract. In British Telecommunications plc v Ticehurst and Thompson [1992] IRLR 219, the Court of Appeal held that a withdrawal of goodwill was in breach of the implied term to serve the employer faithfully.
Suing for damages
Where an authority suffers loss as a result of industrial