Today Ian Norris’s battle against extradition to the United States comes to a head in the House of Lords. In personal terms, the hearing is the climax of a nightmare that has dominated the lives of the former chief executive, his wife and family for five years.

As Sheila Norris puts it: “You don’t believe something like this could happen. It was a complete shock. We just live day to day — we don’t plan for the future.”

But the case has ramifications that go far wider than the couple’s personal lives. It will be the first test before Britain’s highest court of the new fast-track extradition arrangements between the United Kingdom and the US and of the ease with which the American prosecuting authorities can extend the long arm of the law to British businessmen and women.

Alistair Graham, Norris’s solicitor and head of litigation at White & Case, said: “It’s a circus. Countless lawyers are animatedly discussing the key points of this case and awaiting the hearing with great excitement. Some of them seem to have forgotten that it involves a man who is the victim of a travesty of justice. If it goes wrong for him there are plenty of others in the pipeline who could be affected.”

Norris, 65, who retired as chief executive officer of Morgan Crucible after a 33-year career working up to the top from the shopfloor, is wanted for alleged price-fixing of carbon products manufactured by Morgan Crucible when he was a senior executive and for allegedly obstructing justice by covering it up. Price-fixing was a widespread commercial practice in Europe at the time. The Americans argue that it defrauded US shareholders.

The prosecutors regard it as a flagship case. Norris is the first UK national the US Department of Justice has sought to extradite on charges of price-fixing. Scott Hammond, the prosecutor leading the case, has described the extradition as a “blockbuster” development and a “significant test case that could see some 30 other businessmen pursued”. He has also said: “To have the UK be the first government to go to bat for us and assist us in seeking extradition is remarkable.”

The kernel of Norris’s case is that there are no grounds for extradition because price-fixing was not a crime under English law when he allegedly did it. Price-fixing, he and his lawyers argue, was outlawed in the UK by a specific offence only in 2003. The US authorities argue that it was nonetheless a crime at the time because it was covered by England’s common-law offence of conspiracy to defraud.

It is crucial that the US authorities can make this link — and show that what Norris did was a crime under UK law.

His extradition is sought under the Extradition Act 2003 — which came into force on January 1, 2004. Under the previous arrangements, the alleged offence had to appear on a list of specified offences serious enough to warrant extradition. Now there are just two requirements: the alleged conduct must be a crime in both the US and the UK — the “dual criminality” test — and must carry a jail term of more than 12 months.

Crucially, the US authorities no longer have to show evidence that a crime was committed, or a prima facie case. Instead, they must simply provide a detailed description of the facts on which the indictment is based. Without a full indictment, however, there is no opportunity for a UK citizen to contest the charges in England.

The NatWest Three were extradited under the same regime but their case did not reach the House of Lords. In their case the US authorities chose to submit prima facie evidence because they had gathered it — although they were not technically required to do so.

What the five law lords (Lord Bingham of Cornhill, Lord Rodger of Earlsferry, Lord Carswell, Lord Eaton-under-Heywood and Lord Neuberger of Abbotsbury) will examine today is whether the common law of conspiracy to defraud can be equated with the offence of price-fixing.

Graham maintains that it can not; that there is a key difference in that the common-law offence requires dishonest behaviour or an intention to do wrong, whereas being in a cartel is a strict liability offence that of itself does not require any evidence of dishonest behaviour to be shown.

It is almost Alice in Wonderland territory. Graham argues that Norris is wanted for actions that were not a crime when he is said to have done them — in breach of a fundamental principle that the law itself must be sufficiently clear so that people know what they are doing is wrong. “Mr Norris cannot be retrospectively prosecuted for an offence that was not then known to be criminal.”

All this is not just of academic legal interest. The Serious Fraud Office has a linked case, also to be heard by the law lords today in connection with pending prosecutions for conspiracy to defraud, that is being brought against drug manufacturers — again because the alleged cartels pre-date the price-fixing offence.

If Norris fails other extraditions may be sought — for different offences that were non-crimes in the UK. Business individuals, lawyers say, may be at risk as never before.

Lawyers, the business community and civil liberties groups such as Justice and Liberty agree. Luke Tolaini, a lawyer at Clifford Chance and chairman of the CBI’s working group on extradition, said: “If the decision goes against Mr Norris there is a risk that this will result in further requests for extradition based on conduct that many thought was immune from prosecution. It will also cause many to wonder why there was a need for a specific price-fixing offence to be introduced in 2003 if it was covered by pre-existing offences.”

Either way, he added, it illustrates “the enthusiasm with which US prosecutors seek to track down foreign defendants and the UK is a soft target for US extradition requests given the relatively low evidential hurdles set for US prosecutors”.

The irony is that the new extradition regime was never intended to apply to white-collar criminals but to tackle terrorist suspects. Caroline Flint, then Home Office minister, said in a House of Commons debate that cases such as price-fixing “would not apply”. Dual criminality, she added, “would have to exist”.

Meanwhile, Ian and Sheila Norris will be in the House of Lords today wondering what the future holds. Mrs Norris, 64, says: “The best part of our retirement has evaporated. You go on, do normal things. But then you are forced to think about it — if a hearing like this is coming up — and it hits you.”

The kind of man who takes misfortune on the chin, Norris is unwilling to talk about the toll on their lives. Nor does he make anything of the impact on his health or that he is now registered disabled because of mobility problems. “I don’t talk about my family — I wouldn’t want anyone to think I’m trying to influence the law lords,” he says. He need not worry — they will look only at the legal merits. And on that score, he seems to have a pretty unanswerable case.

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