At the village school May Day fayre yesterday there were new signs on the bouncy castles, saying that parents must supervise their children at all times. Is this a legal requirement or just common sense?

I suspect it's a result of the court case last week in which Sam Harris, who was injured on a bouncy castle, sued the couple who'd hired it, and won £1m compensation. I'm not clear whether this is money that's needed for his care, or just a windfall. It will be covered by the defendants' house insurance, which is strange considering it didn't happen on their property. Good news for the defendants, bad news for those of us whose insurance premia will go up to cover it.

My mother-in-law knows the defendants and told us more about what happened. The Perry family hired the castle along with some other equipment for their triplets' birthday party. Because their garden wasn't big enough, they arranged the use of the field behind their home. Sam Harris happened to be playing in the field, with his father, and wanted to bounce. The Perrys said he couldn't, as he wasn't attending the party, but he went on the castle anyway. (He has Asperger's Syndrome which apparently means he doesn't always listen or understand instructions; the judge said this was irrelevant, curiously. Mrs Perry's back was turned; the judge decided this was relevant.) Another boy did a somersault and accidentally kicked Sam, as a result of which he sustained serious head injuries.

Mark Jerram, founder of the British Inflatable Hirers Alliance (BIHA) said the outcome of the case came as little surprise and reflected the blame culture of modern Britain.

Which brings me back to the signs. The judge rejected the Perrys' argument that Mr Harris should have supervised his son. So why are we now asked to do so? Sometimes the law (or its arbitraters) is a ass.