.It is well known that going to court can drive you mad. These days, legal reporters can't walk down the street without people thrusting files of papers at them. You long to tell these litigants to accept defeat and cut their losses. But it's too late – they're gripped by an obsession.

They speak with awe of what they call "section 42 orders". Section 42 of the Supreme Court Act 1997 allows the court to make an order preventing a person from starting any further legal actions without the court's permission. This draconian power is to be used sparingly; the court must first be persuaded by the Attorney-General that the individual has "instituted vexatious proceedings… habitually, persistently and without any reasonable ground".

Declaring people vexatious litigants effectively bans them from using the courts. But sometimes that's not enough. On 14 December last year Dame Elizabeth Butler-Sloss, president of the High Court Family Division, ordered a father from north-west London involved in contested divorce proceedings to stop making any more applications to the court about his children without permission. That clearly didn't do the trick because a week later, the judge banned him from even entering the law courts, except to attend an appeal. He now stands outside, shouting at passers-by and irritating reporters.

The courts probably declare a dozen or so people vexatious litigants every year. A good example was Geoffrey Scriven, a well-spoken and forceful businessman. His problems began in the early 1990s when his wife obtained a divorce and financial provision from him. He began by accusing her solicitors of fraud, conspiracy and perjury after her divorce petition was wrongly backdated. When that action didn't produce the results he had hoped for Scriven issued the first of around a dozen writs against lawyers, judges and politicians, accusing them of conspiracy to pervert the course of justice and high treason.

Scriven had also faced prison for breaching an undertaking not to "scandalise the court". Lord Justice Simon Brown wisely declined to make a martyr of him, explaining that these days "a wry smile" was judges' usual response to allegations that they were all part of a legal mafia. Scandalum magnatum is an archaic form of contempt which was last used in 1931 to deal with an editor who suggested a judge "could hardly be altogether unbiased" about legislation he had helped steer through Parliament while he was one of the government's law officers.

Scriven's best point, as they say in court, related to what he called "secret briefings". These are summaries given to judges of appeals they are about to hear. They're prepared by judicial assistants – young lawyers briefly seconded to the courts at the start of their careers. Nobody would deny the hard-pressed judge a bit of help on where to find the relevant papers, but unless these summaries are made available to the parties there will always be a suspicion that a busy judge will pay too much attention to the views of an ambitious assistant on how the case should be decided.

Scriven need not have worried about the urgent note handed to Lord Brown towards the end of a long morning. As the judge explained, it asked him what sandwiches he wanted for his lunch.

Joshua Rozenberg is the BBC's legal affairs correspondent. He can be contacted at