Recently I received a cause invitation from an old school friend on Facebook. The cause was to support micro-chipping of all paedophiles. I rejected that invitation. All I could think of was the microchip embedded in my Labrador. The way I understand that chip to work is that if someone finds my dog wandering the streets they can take him to a vet or the RSPCA who will then scan the chip and return him to me. The obvious question seemed to be: how would such a measure help protect children? After all, protection of children is the goal articulated in the mission statement of this cause.