One of the best arguments against statutory regulation of the press is that most of the abuses the Leveson inquiry was set up to examine, such as phone-hacking, bribery and the corruption of public officials, are already illegal. But, most obviously in the case of News International, the law has too often proved feeble in the face of media pressure. At least one reason for this is NI's overweening dominance of the market; even after the closure of the News of the World, it still commands 34 per of newspaper circulation. It's also worth remembering that had it not been for the Milly Dowler phone-hacking revelations, News Corporation would almost certainly have acquired 100 per cent of BSkyB.
In views of this, it's worth asking what (if anything) the Leveson report will say about media ownership, an issue that has been little discussed in recent weeks. When Ed Miliband gave evidence to the inquiry in June, he called for  a cap of between 20-30 per cent on newspaper market share, a measure that would entail the break-up of News International. If Miliband wants to burnish his radical credentials, he should return to this subject when he responds to David Cameron tomorrow.