The outcome of any legal action by the CWU against Royal Mail's use of temps is by no means certain

Royal Mail has responded to its own strikes by announcing it will employ 30,000 temporary workers to clear the backlog of post. The CWU has argued that the engagement of such workers is illegal and it is currently considering pursuing an injunction in the High Court. Leeds City Council has managed to provide some sporadic bin collections through the use of private firms - a move also denounced as illegal by unions Unison and GMB.

So what exactly can employers do to reduce the impact on their business and customers if part of their workforce goes on strike?

The Conduct of Employment Agency and Business Regulations 2003 state that it is illegal for agencies to supply workers to undertake duties normally performed by a worker who is involved in a strike or is covering for a striking employee, providing the industrial action is official. Any agency that does this opens itself up to civil and criminal proceedings which, in the case of the latter, can result in either a fine of up to £5,000 on summary conviction in a magistrates court, or an unlimited fine if found guilty in the Crown Court.

The Employment Agency Standards Inspectorate is responsible for enforcing these regulations and pursuing any offenders. It has stated that each worker that is hired through an agency is considered to be a separate offence and therefore can incur a separate fine. The provision of any significant portion of the 30,000 workers that the Royal Mail are contemplating engaging could therefore expose an agency (or agencies) to massive fines. Since the act would be a criminal offence, there would be no possibility of the agencies gaining any meaningful indemnity or contractual insurance against these losses from Royal Mail.

It is important to note that these regulations are aimed solely at the agencies who supply the workers and not at the end-user client. On this basis, it seems that Royal Mail could directly recruit the workers, thereby avoiding all legal liability for doing so. It would appear that this is the option adopted by Leeds City Council in directly contracting the services of private waste collection companies.  However, this is a complex and untested area of law around which there can be few guarantees. Additionally, for a large employer needing such a volume of workers in a short space of time, arranging the recruitment in-house may simply not be an option.

Royal Mail (if it carries through its proposal) is adopting a different tactic. It claims that the temporary workers are not actually performing the tasks of the striking workers and therefore cannot be seen as illegal replacements. It is normal for the Royal Mail to employ 15,000 temporary workers over the Christmas period to deal with the increased workload. As such, Royal Mail claims that none of these additional workers will be performing the duties of those on strike.

The CWU strongly opposes this stance and has pointed out that the seasonal workers would not usually start work so early. They further claim that, aside from inflaming tensions further still, the temporary workers hired to clear the backlog will inevitably end up performing the functions of striking workers.

This is a difficult area of law and it is impossible to say with any great certainty how a court would respond to the hiring of workers in these circumstances. Any action brought before the courts would take a significant amount of time to be decided and the union's legal standing to bring such a claim is questionable. However, it could conceivably be argued that the Royal Mail is assisting in the commissioning of a criminal/civil offence and doubtless the CWU's lawyers are considering what, if any, action they can take. Unless the CWU manages to secure an injunction, Royal Mail will be able to continue to employ such workers in the short to medium term, thereby diminishing the impact of the industrial action.

It seems likely that at least some part of the Royal Mail dispute over temporary workers will appear before the courts. It is hoped that this will provide some welcome clarification in this difficult and relatively unexplored area of law.

Nick Hurley is a partner and James Hall a trainee solicitor in the Employment and Pensions Group at Charles Russell LLP