An employment appeal tribunal has backed a union claim that women should be entitled to the same level of unsocial hours payments as men.

Unison has been battling for six years alongside female workers from St Helens and Knowsley NHS Trust in Merseyside for equal pay.

The legal action was originally rejected at a tribunal court in Newcastle. Unison appealed and said that Justice Laura Cox, at the Employment Appeal Tribunal in London, had ruled in their favour.

A court spokesman confirmed the result which will see the appeal for equal pay return to Newcastle.

The decision paves the way for women at the trust and at other hospitals to challenge pay discrimination on the same grounds.

The women, working as healthcare assistants, domestic supervisors, and on reception, were paid time and one third for working on a Saturday, and time and two thirds for working on Sundays and bank holidays.

But the men were paid at a higher rate of time and a half for Saturdays and double time for Sundays and bank holidays.

The trust claimed that unsocial hours payments were part of their staff’s normal working week, and that payments for these hours could not be separated out from basic pay.

The appeal judge today backed Unison’s claim that unsocial hours payments are a separate term of the employment contract, and can be directly compared.

Unison said the case sets an important precedent, giving women at this trust and others hope that they, too, can challenge unsocial hours payments that are more generous to men.

A trust spokesman said: “A number of trusts are being used as test cases for national equal pay challenges regarding previous NHS pay arrangements which were superseded in October 2004.

“The ruling concerns a minor technical issue regarding unsocial hours payments which do not form part of the new NHS pay arrangements.”