It's thought around 80 bereaved families are affected. The police say they're looking into it - another self-investigation, another bucket of whitewash - but they are distancing themselves by saying it was mainly in the 70s and 80s.
Firstly, that does not alter the morality one iota. Secondly, it is untrue. Whilst the children themselves were born in those years, the identity theft came later. One officer, known as Pete Black, did it in the 90s. He infiltrated anti-racist groups before moving on to campaigns for justice for black people who died in custody or whose death had been under-investigated. Another case was an officer from the 2000s.
WHY DO IT AT ALL?
The idea was that if activists ever researched a police spy's background to check out whether they were who they claimed to be, they would come across the birth record of a real child.
But the obvious problem is that there is also a death certificate waiting to be found. Did they really think people suspicious enough to look for birth certificates would not go further? The case of John Dines proves that, as you'd expect, they would and they did.
Later spies who simply made up a name - Mark Kennedy appears to be one, using his real date of birth to be 'Mark Stone' - had no such flaw. They didn't have a birth certificate, but there are numerous plausible reasons for that, such as being adopted or born abroad. These would also fit with undercover officers' prediliction for stories of a disturbed childhood.
Peter Blexley, a former undercover officer for a different unit investigating serious crime, told the [Radio 4 Today] programme: "I cannot for the life of me comprehend why anyone would want to adopt an identity, rather than create one."
The only plausible reason I can think of is the same one that anybody wants a birth certificate for - to prove an identity to authorities. In an era when the state was dealing with the Cold War and Northern Ireland, perhaps the government thought infiltration of lefty parties, peace activists and trade unionists was unworthy of equipping with the full gamut of false identity documents. Could it be that the undercover officers weren't issued with stuff like fake passports and bank accounts, and resorted to fraudulently applying for them?
Another officer who used a dead child's identity says it was done for 'the greater good' but neglects to tell us what that good is and why it couldn't be achieved by other means.
THE BIG QUESTION
The identity theft of dead children is ghoulish and is further evidence of the institutionalised callousness and arrogance with which the police treat the public they supposedly serve, as if that wasn't already amply illustrated by the way they intrude upon the living.
Presumably they thought that, like the women with whom they had long-term relationships and fathered children, the people they were abusing would never find the full details and catch up with them.
As Pete Black says himself, to search your house they have to get a warrant. To bug your house or tap your phone they have to have approval from the Home Secretary. But to live in your house, hear all your calls, integrate into your family, be your quasi-marital partner, have a child that they know they'll leave you to bring up alone from pre-school age onwards, that just requires the police to decide they want to do it. But that is not the issue.
The big question in the political policing scandal is: who ordered it? Do the police make up these missions for themselves or are they given ideas, directions and commands from political sources? If so, is that the government of the day? An international mix of governments and security services?
The phone hacking scandal caused a storm with politicians clamouring for a public inquiry. There is no way in which the spycops scandal is not a greater invasion of lives and yet politicians (outside the Green Party) are staying deafeningly silent. If you want to know who was complicit and culpable, you should usually look for who is turning away, whistling, hoping not to be noticed.
THE JUSTICE TO COME
The people whose lives have been affected - the women abused for years at a time, the political campaigns undermined and now the grieving families of dead children - have suffered a double injustice.
Firstly there was what was done to them and then there's the wilful obstruction of justice by the police. Amongst the self-investigations is one by the Department of Professional Standards. They are contacting people who were spied on and asking for their assistance whilst simultaneously saying they 'neither confirm nor deny' that the spy was a police officer.
Why would an internal police body be asking about someone who wasn't a police officer? It is an insult to the intelligence of their victims and a crude legal trick to avoid accountability. We all know what went on but if you can't prove that they were a cop, how can you sue police chiefs for doing it? We still don't even have real names for half of the exposed officers.
The increasing likelihood of a public enquiry is good, though that would not be the end. There were two of those for Hillsborough and they failed.
PERSIST AND PREVAIL
This is a justice campaign. People who suffered far worse double injustices - such as the Hillsborough families or the Lawrence family - also got tired at times, and people outside stopped being interested.
But they held on to their outrage, and each new avenue, each attempted assault on the castle would bring a new smidgen of information. And whilst nothing can undo what was done, there can be justice. Truth can be told, those responsible can be brought to account, and future deeds of the same ilk can be prevented.
The peculiar thing about justice campaigns is that if they persist they tend to win. Maybe the authorities give up when there's no careers on the line any more because all those responsible are retired or dead. Or maybe the irritation builds up into a serious discrediting and the continuation of that is worse than letting the truth be told.
Either way, the lesson seems clear. This will not be over soon, and just because the facts become familiar does not make them less of an outrage.