This sort of abuse of individual freedom and rights has come about with the introduction of the Sex Offences Act, 2003. The three largest countries in the EU, Germany, France and Italy, whose citizens are also affected have declared that this act breaches UK and EU law and they are backed by the European Court and even our own High Court is unhappy with it. This is what is behind David Cameron's wish to get rid of the Human Rights Act and replace it with his own so called Bill of Rights, since the main breach of rights is against the rights act. He was just using Abu Hamza as an excuse.
A sample of that idiotically illegal Sex Offences Act from the sentencing guidelines is Section 2B.
Under that any non-sexual touching of a child is liable to a guideline sentence of 26 weeks prison if the child is under 13. The sentencing range for the judges discretion is 4 weeks to 18 months. Up to a year and a half for touching an under 13 year old's arm or shoulder for example if permission was not asked first! This is why medics, teachers etc often ask a child first if it's ok to touch, it's for their own safety.
And for this as for any other so called sex offence, being placed on the sex offenders register is mandatory, the periods anything from 3 to 7 years for these lesser "offences".
Of course the chance of being prosecuted for an innocent touch is small, but this shows how if suspicion is aroused by someone or if a false accusation is made, the innocent accused person is very likely to be convicted and imprisoned.
The outcome of this silly law is that it's very difficult to get any man to work with children. Despite every effort primary school children are being almost exclusively taught by females, and boys doing scouting more often than not have female scout leaders. The authorities know and have said this is an unhealthy way to raise children, especially in these days of so many single mothers, but the damage is done, It would take many years to reverse the situation and there's no signs of the government doing anything other than more damage.