Unite alleges that the charity sacked Teresa Santucci, a development manager who had worked for the organisation for 19 years and was a union shop steward, "on the spot without a single allegation being levelled against her". The union claims she was not the subject of any investigation, capability procedure or disciplinary procedure.
But a spokesman for Peabody said the claims that her employment was terminated because of her disability or because she was involved in union activities were "categorically untrue".
He said the decision to terminate Santucci’s employment "had absolutely nothing to do with her disability or union activities".
"It was entirely due to her performance," he said. "Teresa's managers have tried, over a number of years, to tackle these performance issues positively and creatively. Regrettably, it has not been possible to remedy the situation.
"It would not be appropriate to comment further while the matter remains unresolved."
Nicky Marcus, regional officer at Unite, alleged that Peabody had decided Santucci, who has repetitive strain injury, was "problematic" and simply decided to get rid of her. "They have not come up with a single allegation other than the notion that she and her manager 'didn't get on'," Marcus said.
"The reality is that she has been victimised because of her disability and because she was a Unite rep who stuck her head above the parapet.
"There is simply no plausible alternative explanation as to why Peabody acted in such an appalling way. Having worked there for 19 years, she was just called in by HR and sacked."