The great news manipulator Alastair Campbell once said that a story was serious if it was in the news for eleven days. This is what the Labour party are doing with the Andy Coulson affair and, so far, succeeding.
People who know more about this than I say that it is not about 'phone tapping, or 'phone hacking which are aparently, different things.
What the News of the World scandal gathering operation was doing is calling famous people's mobiles at times they would be talking or have them turned off. You get put through to the voicemail or secretarial sevice, and inserting a code allows the owner, remotely, to access his messages. Most people, apprently, don't bother to change the '0000' which is the default setting, so the reporter hears the messages.
If you are burgled and you tell the police (should they express any interest) that you left the house unlocked, you get a stern talking to. But despite the fact that a certain amount of negligence has taken place, intruding on your private messages, like burglary, is a crime. Two reporters went to prison for it. Coulson resigned as editor of the News of the World but says he knew nothing about it at the time and therefore the police can't charge him.
All this may be true but some people will be asking whether Mr. Cameron, knowing this, wasn't a little rash to employ Mr Coulson.
My guess is that this story will die out, but not quite yet.