Good old VBS & IBB
One of the things about VBS is that is was about the suitability of a person to work with children or vulnerable people in general. The IBB were responsible for actually barring a person, and you could be barred for more than abuse.
You also would have your registration suspended whilst you were investigated, and as many a teacher will tell you, the complaints are often spurious, and malicious. You could be barred because of your criminal record, which might be anything from theft to drug dealing, even to the level of cautions, which by the way also come up on CRB checks.
As paranoid granny proves, it wouldn't matter why someone was barred, she would assume the worst, and probably tell all her friends. It wasn't long before VBS went into development that someone was lynched because he was thought to be a pedophile.
The good thing about VBS was it was a once only application process, that then monitored your criminal activities, rather than CRB checks which are required for each organisation you work with, and need to be repeated regularly to the financial benefit of Capita. The bad thing was that once you were on it, you were on it, and it would have been very easy to widen the scope to cover just about any offence. Drink Driving conviction, sorry mate not having you teach my children, and so on, just a matter of a minor tweak to the law and the system.
VBS was never fully implemented, and then scrapped, but the whole CRB thing is up for renewal, it's probably Capita's to loose.