No-one likes bad things to happen. Witnesses to bad things have an obligation to act that is usually commensurate with risk. You wouldn’t intervene in a gang fight in a dark alley, for instance, but might report a distressed dog in a hot car.

Yet there is a growing tendency to turn this instinct into law. As the police withdraw, we are the new crimefighters.

The latest is the imposition on teachers and health workers to report cases of female genital mutilation . Most people in those professions, suitably horrified, would be inclined to act anyway – but if they do not, they could face disciplinary action.

This follows other calls to make mandatory reporting of child abuse suspicions legally enforceable ; failure to do so, a criminal offence.

This shift from self-willed imperative to statutory one, is alarming.

Firstly, it makes people’s thoughts and actions the state’s business. Motives are tricky to understand, impossible to legislate for.

What is a “suspicion”? The product of an over-active imagination? A cynical attack? A well-meaning (but potentially devastating) error?

Secondly, mandatory reporting corrupts the nature of the relationship between two individuals – professional and victim.

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Would a girl, for example, trust a teacher with the confidence of her FGM fears if she understood that she was not telling Miss Faversham but the entire legal apparatus?

Thirdly, this trend distorts the nature of the relationship between an individual and the state, turning it into one of mistrust and coercion.

The simplest way for the state to change this delicate dynamic is to smuggle in these obligations under the cloak of a highly emotive issue. Thus the arguments are conflated – disagree with mandatory reporting, you must be complicit with the abuser.

The move can be seen for what it is by transferring the same argument onto recycle bin usage for example. There, one feels a strange kinship with the individual against the government. The instinct is to be suspicious of an intrusive state.

The arena of modern life that is not pebble-dashed with legal obligations is precious and tiny at best but, at least, within its boundaries, people are still free to exercise discretion. We surrender that liberty at our peril.