A Metropolitan Police officer has won a test legal victory that dyslexia is a disability in the eyes of the law.

Chief Inspector David Paterson – who gained promotion despite his condition – won a ruling from the Employment Appeal Tribunal that he is “a disabled person”.

Mr Paterson joined the police in Epsom in 1983, became a sergeant in 1989 and was made a chief inspector in Vauxhall in 1999. But in 2004 he discovered that he suffered from dyslexia and accused the Met of discriminating against him. He claimed that the force failed to make reasonable adjustments, particularly in the processes for deciding whether he might be promoted to superintendent.

An employment tribunal had ruled earlier that Mr Paterson was not disabled within the terms of the Disability Discrimination Act 1996. It found that dyslexia did not have a “substantial adverse effect on his ability to carry out day-to-day activities”.

But the Employment Appeal Tribunal, headed by Mr Justice Elias, one of the country’s senior High Court judges, has now ruled that, as his professional advancement depended upon his sitting examinations, the dyslexia did constitute a “substantial” impairment.

In its decision just made public, Mr Justice Elias said: “In our view, carrying out an assessment or examination is properly to be described as a normal, day-to-day activity. Moreover, in our view the act of reading and comprehension is itself a normal, day-to-day activity.

He said that the evidence, which the tribunal accepted, was that Mr Paterson was “disadvantaged to the extent of requiring 25 per cent extra time to do an assessment”. As a result, he said that it “inevitably followed that there was a substantial adverse effect on normal, day-to-day activities”.

The case now goes back to the tribunal to decide if Mr Paterson’s claim for discrimination should succeed.

Mohini Bharania, Mr Paterson’s solicitor at Russell Jones & Walker, said: “This is a landmark judgment, which has the potential to benefit the millions of dyslexia sufferers in the UK who are perfectly capable employees, but who may struggle with exams.”

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