Some years ago I attended a day course on media law. It was taught by a former journalist who had later taken a law degree, and what a remember most from the day is his stories of the various scams he used to get up to as a young reporter. In the days when you had to phone your copy in, the ability to extract free calls from a public phone was a useful way of making those expenses go further.
But he did cover the basics of libel, parliamentary privilege and qualified privilege, and something else he said has stayed with me. It was that the judges were clearly determined to create a new tort of privacy and that we should keep an eye on how this developed through case law.
How right he was.
At the heart of the current farce over the law on privacy lies this judicial activism. Privacy law has been developed through judgments in the courts and not through debate in Parliament or wider society.
For many on the left, who reason that the public is irredeemably conservative in its social views, this has been rather attractive. Battles they dare not fight or could not win at Westminster could be fought instead in more patrician European institutions.
Certainly, a despair of ever winning in Britain again was one of the reason for Labour's embrace of the European ideal under Neil Kinnock.
Add to this despair amongst politicians the instinctive arrogance of the legal profession and you have a powerful and toxic brew.
I am a Liberal and am instinctively in favour of free debate, whether in the press or on Twitter. I find the demand to prove a "public interest" before something can be published absurd. It is those who favour censorship who should be forced to show it is in the public interest.
Finally, we are told that blackmail is an important element in the case that has caused all the trouble. But blackmail is a serious criminal offence. If there is convincing evidence that someone has committed blackmail then he or she should be arrested and charge.
It should not be possible to raise the spectre of blackmail, gain an injunction and then leave the matter hanging in the air for ever after. You would not allow it with murder: why allow it with blackmail.
All of which is a way of saying that I fully support John Hemming's actions in the Commons today.