Whether people agree or disagree with what the Blair government did with regard to Iraq, I don’t think anyone can say we have not answered questions on the subject.

In addition to the four inquiries to which I have testified, I have been asked about the subject in hundreds if not thousands of interviews and public meetings, and have always sought to answer questions fully and truthfully.

So whilst I respect the right of anyone to say the government did the wrong thing – though I disagree – I cannot accept the view of those who have been tweeting this afternoon that I have not answered questions on the subject. I have and I always will.

The issue arose because I asked Piers Morgan via twitter what stories were delivered to the Mirror about myself and Peter Mandelson – Piers was editor at the time – when the paper was paying fairly sizeable sums to private detective Jonathan Rees.

At first the question went ignored, but I know that Piers prides himself on not running away, so I knew if I persevered and repeated the question that eventually he would say something.

When he did it was to turn to  attack as the best form of defence. I don’t have a problem with that but he has to accept that saying the war in Iraq was illegal – his view and that of others, but not of the Attorney General at the time – is not an answer to the question I was asking.

I am not remotely suggesting that in terms of seriousness of an issue, the payments paid by a newspaper to private eyes are on a par with a government committing its citizens to war. But I do think the nature of our media is an important issue for our democracy as a whole, and there are a lot of unanswered questions both in the phone-hacking saga, and in the Rees affair, and what both say about Britain’s press and its cavalier and self-serving regard for the rule of law.

And I don’t think the questions are going to go away, especially following David Cameron’s answer to Labour MP Tom Watson in the Commons on Wednesday, when the PM signalled the police should investigate as widely as the evidence takes them.

I have seen the invoices relating to me and to many others Rees was asked by the Mirror and by other papers to look into. Piers is right that the invoices themselves do not show illegality. They speak of services rendered, information supplied, inquiries made. But the sums involved, when you tot them all up, are fairly big. Newspapers are not nearly as generous with freelance payments as they used to be, so we are entitled to assume Rees was either doing things journalists could or would not, or providing information of some significance.

These invoices and other information only came to light because Rees was involved in a murder case and he was under investigation by police for matters essentially unrelated to his work for the media.

But Piers, who whatever people think is actually one of the more intelligent members of his profession, surely agrees with me that if Rees’s activity related to any other walk of our national life but the press, he would be the subject of rather more coverage than he is getting; and indeed that the press would be at the front of the queue asking the questions.

As it happens, despite our many ups and downs when he was an editor and I was in Downing Street, I find it very hard to dislike Piers, (I have friends who regularly tell me off for it) and I am very pleased for him that he has made it big in the States. I was delighted to be invited to his wedding last year, and am happy for him and Celia that she is pregnant.

I am also prepared to accept, as he said in one of the many tweets he sent me as I was watching the rain fall at Queen’s Club, that he did not personally know Rees; and though he had a few things to say about Iraq on twitter today, I did not join in with those who were reminding him of the so-called fake photos scandal, insider share dealing or any of the rest of it.

We will doubtless carry on with the twitterbanter. But the fact remains that Rees was paid substantial sums to provide information and deliver services in relation to me and people close to me. Piers cannot be surprised that I have more than a passing interest in knowing what it might have been, and also in knowing whether the law was broken in his obtaining of it.

So Piers can continue to say we did the wrong thing in Iraq and that we should all be dragged off to the Hague for a war crimes trial. But in the meantime I think his former paper does owe this former employee, and many other people, a few answers about what it got up to when Rees was on the payroll.

Ps, I cannot pretend Henry Porter is one of my favourite people or journalists but amid the general media blackout on media wrongdoing, at least he is having a go. Here is the piece he wrote for The Observer today. Worth a read.