The veteran business manager of a Sunderland school was unfairly dismissed after being stripped of her responsibilities and demoted to "officey things".
Zena Dickenson worked at Easington Lane Primary School for 21 years and had charge over a staff of 15 and a budget of £1.2 million.
But in November 2015 she was concerned about funding shortfalls and mentioned to a colleague that redundancies might be in the offing.
The school's response was to suspend her from duty in December that year and Ms Dickenson faced a governors' disciplinary panel.
The governors decided not to take any formal action against her and she was allowed to return to work in February 2016.
But, when she turned up to resume her duties, she discovered that her security pass had been disabled, an Employment Tribunal heard.
She had to be let in by a teaching assistant and was told to wait in reception, said employment judge James Shepherd.
She was told that her performance was under review and she would not have any line management responsibilities until that was done.
Informed that she would be "updating the school's database" until the review was completed, she asked if she would basically be a receptionist.
And one manager responded that "they wouldn't call it that", but that she "could do officey things".
At that, Ms Dickenson became "distressed" and, in April 2016, she handed in her resignation, saying she had "no choice".
Her barrister, Edward Legard, described her treatment after so many years' service as "reprehensible".
"She was demoted, turned out of her office and stripped of all her main job functions without warning, consent or discussion," he argued
Upholding her unfair dismissal claim, Judge Shepherd ruled that the decision to suspend her was "inappropriate and unreasonable".
"When she returned to work, her financial duties were removed, her line management responsibilities were removed and she no longer had an office.
"She was told that she was expected to work in the main office at reception, updating the school's database."
By treating her in the way it did, the school breached the duty of "mutual trust and confidence" that it owed her, the judge ruled.
She was entitled to resign in response and her constructive dismissal was "outside the band of reasonable responses" to be expected of the school.
Ms Dickenson's claim of age discrimination was rejected although Judge Shepherd's ruling entitles to her compensation for the loss of her career.
The amount of her payout has yet to be assessed.