The long-running legal challenge the introduction of employment tribunal fees is nearing its conclusion following a hearing at the Supreme Court.

A two-day hearing, pitting trade union Unison against the lord chancellor, concluded today.

If the case goes in favour of the government it will mark the end of the appeal process for the union, which has been enagaged in a four year legal battle. Unison’s case was first heard in the High Court in 2013 and the Court of Appeal in April 2015. However, its claims were dismissed both times.

Tribunal fees were introduced in July 2013. Fees start at around £160, and increase to between £230 and £950 for further hearings.

Unison claims that the introduction of fees has stopped thousands of employees, particularly those on low incomes, from getting justice if they are badly treated by their employers. The case also asks whether fees breaches the EU law principle of effectiveness, and whether the policy is indirectly indiscriminatory.

Unison was represented by Dinah Rose QC of Blackstone Chambers instructed by Unison’s in-house legal officer, solicitor Shantha David. The Lord Chancellor was represented by David Barr QC, of Temple Garden Chambers.

Summing up, Rose said ‘it is unlawful for the lord chancellor, by delegated legislation, to introduce a fee scheme that makes enforcement of UK employment law rights uneconomical’.

In earlier arguments she said the fees scheme had ‘clearly had a very serious impact on rights of access to justice, shutting out large numbers of the small claims that the tribunal was set up to hear.’

Barr said it was ‘entirely justifiable’ to charge different fees for different levels of service. He added that all alternative systems would be worse than the current ‘two tiered system’.

Judgment is expected within six months.