"No 11-year-old child should have to see his parent treated like a criminal for no reason whatsoever."

"And no Englishman enjoying a ramble with his son should face examination by police at the roadside on suspicion of being a sexual predator. Astonishingly – and I find it difficult, some days after the event, to comprehend that I am writing this now – this is what has just  happened to my son and me."

Writes the well-known author Will Self.