Industrial Action, at first glance is unlawful, since the employees involved will breach their contracts of employment and any trade union calling the strike will also commit the tort of inducing a breach of contract. However, if there is a genuine "trade dispute" and the industrial action is organised in accordance with the strict rules set out in legislation, the Industrial Action will be immune from legal action.
- Lack of a genuine trade dispute
In order for a trade union to organise Industrial Action lawfully it must be in contemplation or furtherance of a trade dispute, i.e. there is a dispute between workers and their employer relating to certain prescribed issues covered in legislation, including terms and conditions of employment, working conditions, disciplinary action and so on. If there is no trade dispute then an employer could reasonably challenge the industrial action. So, often, a “political” strike may be unlawful.
- Industrial action taken for a prohibited purpose
Union authorised Industrial Action will be unlawful if it is for any of the following purposes: to require the employer to employ only union members; to support employees dismissed during unofficial Industrial Action; to induce an employer to require the supplier to use only union members; or to induce an employer to refuse to deal with a supplier on grounds related to union membership.
- Prohibited Industrial Action that has been endorsed by the union, including secondary action and unlawful picketing
Secondary Industrial Action is unlawful and does not qualify for immunity and occurs where an organisation A is in dispute with its employees over pay and a union official threatens that unless it gives in, it will ask the workers of another organisation B not to deliver supplies. Here the breach of the employment contract relates to that “secondary” employer B and its employees, who are not party to the dispute between the union and the organisation.
- Breach of balloting and notification requirements by the union
Where a trade union calls for industrial action, it must have the majority support of a properly-organised ballot and must comply with a number of procedural requirements, otherwise the employer will have grounds to seek an injunction to prevent the action going ahead. These include the following:
- The employer must be provided with a notice of ballot no later than 7 days before the ballot, and a copying of voting papers no later than 3 days before the ballot.
- The ballot must be held in accordance with balloting rules and an independant scrutineer should manage this and report on the conduct of the ballot within 4 weeks.
- All those entitled to vote must be allowed to vote.
- There must be a turnout of at least 50% of the union members entitled to vote.
- In ordinary ballots, a simple majority of 50% supporting the ballot is required. But in "important public services" (which includes non-fee paying schools and academies) the required level of support is 40% of those who turnout.
- Reasonable steps must be taken to announce the ballot.
- Notice of Industrial Action must be served on the relevant employer at least 14 days before the start of the Industrial Action.
- The Industrial Action must be started within 4 weeks of the date the ballot closed.