Yesterday evening there appeared on Twitter an account which purported to disclose the details of various supposed "superinjunctions".

None of the apparent revelations seemed to be in the public interest. Instead, it seemed a depressing publication of personal information, which, whether true or false, was a needless intrusion into the private lives of those involved. One basis of a civilised and liberal society is that information that only concerns the private lives of those involved should remain privy to them, unless there is a public interest to the contrary. Everyone needs a private space, even celebrities and politicians.

At closer look, some of the examples were, in fact, based on quite normal injunctions which had been reported in the media; a couple of examples were based on current rumours and educated guesswork; and a couple were so unlikely that they appeared to be fabricated. Overall, it looked like a hoax account insofar as it claimed to be giving out reliable information on "superinjunctions". The only slightly interesting point was the number of media and legal twitterers who were suddenly looking at the account not really knowing what could -- and should -- be done with these trivial and personal allegations. Such observers were right to be concerned: one false move could well have been a contempt of court or a fresh defamatory publication.

The background to all this is that the word "superinjunction" now has a special and exciting quality. This is strange as, in one important way, "superinjunctions" do not really exist. What the High Court can offer are injunctions: court orders directed at parties so as to prevent certain specified courses of action. A "superinjunction" is just a normal injunction but with strict terms, and it is not an entirely new legal creature. Strict injunctions are as old as the equitable jurisdiction of the High Court.

Not even in colloquial terms is there an agreed description of what is a "superinjunction". The best practical definition is that it is an injunction, the terms of which mean that disclosure to a third party that the injunction even exists would itself be a breach of the injunction. Sometimes such court orders are entirely proper. In the criminal and human rights context, the analogous "Mary Bell" orders prevent disclosure of details which would point to the identity of a former criminal. In the civil context, such strict injunctions are granted in rare cases where the type of legal right being protected -- confidentiality, legal professional privilege, private information -- is such that the right would itself be lost if the existence of the injunction was revealed.

Unless the contention is that the courts should never protect such legal rights -- thus effectively rendering the law protecting confidentiality, legal professional privilege, private information as having no practical effect in certain rare situations -- then there is a role for so-called "superinjunctions", though they should only be granted sparingly and always for good reason.

It should also be noted that "superinjunctions" are exceptional in libel claims, and when one hears a pundit casually conflate the two issues -- for example, the notorious Trafigura superinjunction was not granted in respect of libel -- then it is usually a sign that the pundit does not actually know what he or she is talking about. Similarly, injunctions where the names of one or more of the parties are simply anonymised are not "superinjunctions" as the fact of the injunction is usually public.

So why is there this current frenzy about "superinjunctions"? Why is the tabloid media desperately seeking to discredit "superinjunctions" in theory and, as far as they dare, in practice? The reason is partly that such court orders undermine a certain unattractive approach to reporting celebrity news. It is also partly because court orders actually work. Unlike with "phone-tapping" and data privacy laws, robust editors and their lawyers cannot blithely disregard the risk of the legal consequences of a breach of an injunction.

But one suspects the primary reason why the tabloid media are now so anxious to undermine the whole notion of "superinjunctions" is that the European Court of Human Rights is expected to hand down its decision in the Mosley case later this week.

The issue in this potentially highly significant case is whether the UK should make it a requirement that before the mainstream media can irrecoverably publish private information, they should first notify the individuals concerned. This sensible and fair approach is deeply opposed by the mainstream media, as the alerted individuals may well immediately apply to the High Court for an injunction to protect their right against private and personal information being wrongly publicised. However, if such injunctions can be discredited in the "Court of Public Opinion" then it is less likely that any adverse judgment in the Mosley case will gain traction.

Ultimately, personal privacy is as much a basic human right as freedom of expression. Neither has an inherent priority over the other. The courts rightly do not presume in favour of one or against the other when the two appear to conflict. "Superinjunctions" are granted in individual cases where the rights of the individuals involved appear to the Courts to warrant an interference with free speech. One hopes that they are not granted too lightly and that, if so, there can be reform as to how the Courts approach such applications.

But we must be wary of the tabloid media seeking to entice us into a frenzy or latter day witch-craze against "superinjunctions" being granted at all. The tabloid media had no proper regard for the basic laws protecting human privacy in the phone-hacking scandal, and so one should be sceptical of their protestations now.

David Allen Green is a media lawyer and legal correspondent to the New Statesman