For a brief time this week, until it was taken down, there was an extraordinary posting on YouTube. It was a covert recording, made by a 34-year-old mother, of her meeting with the social worker who wants to take her next baby into care.

Had it been staged, critics would have called it a caricature. A robotic official orders the sobbing mother to stay in the hospital until his colleagues come to remove her new baby. He refuses her desperate pleas to be monitored with the baby at home. He explains in the tones of a traffic warden the inconvenience of delivering her breast milk. He then lets drop an astonishing admission: that Calderdale Council is pursuing a court order despite there being “no immediate risk to your child from yourselves”. Will he say that in court? We will not know, of course, for the court will sit in secret.

Such a chilling drama plays to our deepest fears of state tyranny. There is something wrong with the system. But posting a conversation on YouTube, out of context, is not the way to right it. The council argues that Vanessa Brookes’s recording falls foul of the Data Protection Act. Her supporters say that she is a victim of social services and justified in publishing what is essentially her own data. But we do not know whether she is a victim. Who is abusing whom here?

Mrs Brookes’s case is not straightforward. She is partially sighted and has suffered bouts of depression. Two of her children have already been adopted. That does not prove that she is an unfit mother - mistakes can be made - but it does explain the council’s interest. Equally, I am told that she and her husband have never been accused of harming any child. But this dribble of incomplete facts is fundamentally unenlightening. All it does is illustrate the torturous trade-offs that the system has to make, and our inability to judge those trade-offs because it is illegal to read family court papers.

How should we treat someone like Mrs Brookes, who has troubles enough to worry social services but has not apparently yet harmed a child? She is one of a growing group of people who are categorised as capable of “emotional abuse”. You can see why the category exists. Ill-treatment comes in many forms, not just cigarette burns. But in that nebulous phrase lurks the potential for great injustice.

“Emotional abuse” has no strict definition in British law. Yet it now accounts for an astounding 21 per cent of all children registered as needing protection, up from 14 per cent in 1997. Last year 6,700 children were put on the child protection register for emotional abuse, compared with only 2,600 for sexual abuse and 5,100 for physical abuse. Both of the latter two categories have been falling steadily. Meanwhile emotional abuse and “neglect” - which replaced the old notion of “grave concern” in 1989 - have been rising. Both are catch-alls. But emotional abuse is especially vague. It covers children who have not been injured, have not complained, and do not come under “emotional neglect”.

The Department of Health defines emotional abuse as “persistent emotional ill-treatment . . . [which] may involve conveying to children that they are worthless or inadequate . . . and may feature age or developmentally inappropriate expectations being placed on children . . . Some level of emotional abuse is involved in all types of ill-treatment of a child, though it may occur alone”.

Local authorities have printed their own, wildly differing, interpretations. In Enfield emotional abuse includes “swearing”, “conditional love” or “discriminatory remarks”. In Nottingham, it is “an ingrained pattern of interaction . . . which it is essential to observe and understand over time”. Under that definition, a baby could never be removed at birth. Nottingham also states that emotional abuse should rarely be a cause for removing a child. Meanwhile the NSPCC, the charity that has never knowingly undersold a statistic, states in its briefing on emotional abuse that “18 per cent of children experience humiliation and/or attacks on self-esteem”. Should we put them all in care, then?

“You’ll know it when you see it - except that you can’t see it” is no way to make law. Abuse literature repeatedly states how often parent and child are unaware of the damage done by their relationship patterns. How do we weigh that damage against the trauma of the conveyor belt of foster care? In most such situations, isn’t removing a child utterly disproportionate?

Just imagine that some social services departments were crusaders, seeing evil parents everywhere but unable to prove conventional abuse. It is plausible that the number of vague allegations would rise, backed by psychiatrists of a similar mindset who are prepared to enter a “maybe”. How else can one explain a 50 per cent rise in emotional abuse cases in ten years? How many of those cases are utterly marginal?

Next, imagine that the rise in these cases had left social workers even more overstretched. They would have less time to monitor children at home and to keep families together. They would also have less time for the hard-core cases. No system can ever protect every child. But the toddler on Haringey’s at-risk register who was found dead last week with fractured ribs, a broken back and two missing fingernails was surely more deserving of removal than those at risk of low self-esteem.

So many cases are gut-wrenchingly complex. We need social workers to be properly accountable. We need the family courts to be open. Mrs Brookes is clearly not perfect, but she deserves to have clear grounds for the removal of her child. Right now, it looks as though around 6,000 people stand accused of abuse, or potential abuse, that no lawyer can even define. That is an appalling vista that we must not continue to hide from public view.

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