Their union, SIPTU, had argued that the company had sought 14 volunteers to cover the event in an improper fashion, without consulting its shop stewards.

The volunteers received a 500 voucher each as an incentive to "ensure service excellence" at the event.

According to the company, it had decided to seek volunteers in this fashion because of the unique nature of the event and the fact that some staff may have had a special interest in golf.

Group 4 Securior told the court that it was "under pressure. . . due to the security arrangements for the event.

The process of allowing staff to volunteer was the only way possible and practical in these circumstances."

However, SIPTU claimed that the company had failed to adhere to its agreed procedures with regard to special events and that its actions undermined the position of its shop stewards.

The court stated in its recommendation that the company's actions "inadvertently gave rise to the union's grievance".

But it said that, in light of the company's undertaking to follow its procedures in the future, it did not recommend compensation payments for SIPTU's members.