The prevailing obsession with equality leads sometimes, like many good intentions, to cruelty and injustice, not least against people with learning disabilities. Last week the newspapers were full of pictures of a sweet-faced boy with Down’s syndrome of about 18, looking much younger, who has been so unjustly treated by the police and the procurator fiscal in Scotland that, most unusually, the Scottish Crown Office has just apologised to his family.

This unfortunate young man, who attends the special needs department of a college in Lanarkshire, allegedly pushed or slapped an Asian girl with special needs on the same course. It was a very minor incident, rather like a playground spat, which I would have expected their course workers to sort out.

That did not happen. A notice was soon placed in a local newspaper - by a person or persons unnamed - asking for witnesses to a “racial assault” at the college on the day in question. Before long the young man was visited at home by the police and charged with assault and racial abuse. Gentle and cheerful as usual, he greeted them with smiles, agreed with everything they said and thanked them for coming to visit him.

Anyone who knows people with Down’s syndrome, as I do, will be aware that they tend to be cooperative and anxious to please, will often say what you appear to want to hear and agree with you enthusiastically, even though they may feel differently. Of course that isn’t true of everyone with Down’s, but it is widespread among them, as with other people with learning disabilities (LDs), for various reasons.

One reason is undoubtedly their sad experience that it is politic to agree with people who have power over them. However much professionals in the field may frown on the word suggestible, the truth is that people with LDs do tend to be suggestible. That could have explained this young man’s confessions to the nice police.

For seven months these charges hung over him. His family say he was terrified of going to jail. As it happened, the Asian girl in question soon admitted that she had scratched her own face to make marks and had referred to herself as a “black-face”. (One wonders what had persuaded her to do that.)

Even if he did slap her and call her racist names, it would be silly and cruel to hold him - or her - responsible. A person with a learning disability is not as responsible for his actions as one of normal intelligence. That’s what a learning disability means - the lifelong handicap of permanently impaired intelligence and understanding, even with the best love and support.

The tragedy is that so many people with LDs – such a very high proportion, perhaps 30% of all offenders - find themselves in police cells or in prison, where they do not in justice belong. They do not deserve to be treated equally with other offenders.

Underlying all this is a dangerous confusion surrounding learning disability. It has to do with the euphemism and denial with which people shield themselves from its hard realities. At one extreme people imagine that people with LDs, particularly those with Down’s, are innocents incapable of being nasty and malicious. That is sentimental nonsense. Typically of this view, a spokeswoman for Down’s Syndrome Scotland said last week: “I have never met any Down’s syndrome [people] who are racist.” Actually, they are likely to adopt the attitudes of those around them.

At the other extreme, particularly among professionals and academics in the field, there is an assumption that people with LDs are just as responsible - equally responsible - for what they do as normal people. David Congdon, head of campaigns and policy at Mencap, said last week that “people with LDs are individuals with opinions who are just as capable as the next person of being racist or committing a crime”. This strikes me as wrong and unjust. It is a different form of denial.

I have strong personal feelings about this. A few years ago I was indirectly involved for many months with a difficult case in which a woman with LDs was frequently hit or pushed and maliciously insulted by a man with LDs living close by. It caused great distress to everyone concerned: to the care workers, families and social workers responsible for resolving the problem. But not once did anyone even mention the police or criminal charges or sexism because, fortunately, everyone understood that the attacks were a direct consequence of the LDs - his and to some extent hers.

The question here is not what people do - of course a person with LDs could do something bad - but how responsible they are for it. To commit a crime, and by extension to be guilty of it, you must in law have a guilty mind, mens rea in Latin. A guilty mind means the understanding and intention of wrongdoing. Clearly most people with LDs would not have mens rea in the same way as someone of normal intelligence. They would not be equally guilty, and probably not guilty at all. As the 18-year-old’s mother said: “How could my boy be racist? He has a mental age of five.” She is entirely right.

Unsurprisingly, perhaps, the learning disability activists dislike the idea of a “mental age”, which links LDs with children and the status of minority. In their loyal and admirable support for people with LDs, they insist on their equality and their equal rights, which has led to a mentality of denial. The recent Mental Incapacity Act, for instance, which affected people with LDs among others, was suddenly, and tellingly, changed under lobby pressure to the Mental Capacity Act. This struck me an unmistakable sign of denial. The universal phrase “learning disability” is itself a form of euphemistic denial.

As usual a cry has gone up for more training for the police to deal better with cases like last week’s. Personally I think more training – of the sort offered these days – would only make things worse. The prevailing orthodoxy in which public servants are trained is one of aggressive egalitarianism, mixed with an obsession with racism, which is all too likely to deflect them from truth, compassion and common sense. This orthodoxy created this mess in the first place.

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