A teacher sacked after showing the horror film Halloween to a class of teenagers should get more than £600,000 compensation for disability discrimination, top judges have ruled.

Philip Grosset was praised for his work as head of English at the Joseph Rowntree School in York, despite his suffering from cystic fibrosis.

But the 47-year-old’s work at the school came to an abrupt end after he showed a class of 15-year-olds the 18-rated horror movie in 2013.

Philip Grosset, a teacher who suffered from cystic fibrosis, has been awarded more than half a million pounds in damages after he was sacked for showing children a horror film

Mr Grosset then won an employment tribunal after arguing he was under huge pressure at the time and the school did not do enough to accommodate his condition.

Following a lengthy and expensive legal battle, three judges at the Court of Appeal today backed the teacher and ordered the council pay him £646,663 in damages.

In his ruling, senior judge Lord Justice Sales said that Mr Grosset intended to ‘use the the film as a vehicle for discussion in the class about construction of narrative.’

‘He did not inform the school that he was going to use an 18-rated film for this purpose,’ said the judge. ‘Nor did he obtain consent from the parents of the pupils concerned.’

Mr Grosset accepted showing the film was a mistake but said he was under huge pressure at the time

After school bosses found out about the Halloween incident, he ‘accepted that showing the film was inappropriate’ and an error of judgment.

But the council sacked him after refusing to accept that his expressions of regret and remorse were sincere.

An Employment Tribunal later found his dismissal had arisen from disability discrimination and awarded him damages.

But the City of York Council appealed the judgment, forcing another costly round of legal arguments.

Lord Justice Sales, sitting with two other judges, today found his workload should have been reduced and his expressions of remorse were sincere.

The school’s English teaching was ‘in disarray’ when Mr Grosset joined, said the judge, but the teacher ‘succeeded in turning round the fortunes of the department.’

In the summer of 2013, the school achieved its best ever GCSE results. But Mr Grosset said that he was subjected to an ever-increasing workload and ‘could not cope’.

The court heard Mr Grosset has turned around the English department at the Joseph Rowntree School in York before his abrupt departure

He had to stick to a gruelling daily exercise regime because of his illness, and feared that he might need lung transplants if his health collapsed.

Had he not been put under so much stress at work, he would have been ‘unlikely in the extreme’ to have shown the film to his pupils, the judge said.

The ruling means the taxpayer is likely to pick up much of the expensive legal costs of the case.