In the case of Bone v North Essex Partnership NHS Foundation Trust [2016], the Court of Appeal reinstated a tribunal’s decision that an employer’s failure to deal with hostility towards a union member was unlawful detriment. Workers are protected against suffering a detriment by any act, or any deliberate failure to act, by their employer if the act or failure to act takes place for the sole or main purpose of preventing or deterring them from taking part in trade union activities at an appropriate time.