A claim for constructive unfair dismissal on grounds of whistle-blowing can only succeed if the whistle-blowing itself was the cause of the forced resignation; it is not sufficient (albeit it may support an "ordinary constructive unfair dismissal claim) if the resignation was forced by some aspect of the employer's reaction to it.
Mrs Price had worked very happily as an office assistant at a small primary school in Surrey for some years until a new head-teacher, a Mrs Clark, began at the school. Mrs Clark's management style upset staff and governors, 2 of whom resigned.
Mrs Price raised a grievance with the chair of governors, a Mr Richardson, that Mrs Clark had bullied her, other members of staff, parents and pupils. It was 4 months before a meeting took place to discuss the issues due to Mr Richardson's work commitments. Her grievance was rejected, it being stated that there was no evidence of bullying against her.