UNITE has hailed a Supreme Court decision on union rights as a “historic” legal judgment after Britain’s highest court backed calls to oppose undermining collective bargaining. 

The union said that the outcome of its six-year case will affect union members across the country after Kostal Ltd, a car components manufacturer from Rotherham, sought to undermine union negotiations by offering unlawful inducements.

After Kostal and Unite signed a union recognition agreement, the next round of wage negotiations in October 2015 resulted in a formal union ballot of members in which 80 per cent voted against the offer. 

The company then wrote directly to members and urged them to accept the offer individually or lose a Christmas bonus worth £270, with workers also having to accept changes to conditions. 

In January 2016, the offer was repeated and then coupled with the threat of dismissal if workers did not accept it.

Over the next two years, the union won two employment tribunals which ruled that both Kostal offers amounted to unlawful inducements, with members awarded over £420,000.

The legal battle continued in June 2019, with these findings overturned at the Court of Appeal – but Wednesday’s Supreme Court overruled this decision. 

Unite said that the judgment will see the workers involved each receiving around £8,000.

General secretary Sharon Graham said that the outcome means no employer can ever offer their employees inducements to undermine union collective bargaining.

She said: “This judgement is a game changer. It means that employers cannot ignore legally established collective bargaining rights just because they suddenly choose to ignore them or subvert them.

“Every worker should realise now that it’s in their interest to be a union member. That is momentous.”

Kostal was approached for comment.