It follows from the Law Lords' decision that at least some of the offences alleged are extradition crimes. It is likely that the Spanish authorities will have made sure their formal request was properly authenticated. It was never argued that the offences were of a political character and the Law Lords rejected the claim that they were within the official duties of a head of state.

The question of compassion is a difficult one. But it is worth noting that that the Crown Prosecution Service works on the basis that the more serious the offence, the more likely it is that a prosecution will be needed in the public interest. Prosecutors also take less account of a defendant's age if he is facing serious charges, such as murder.

Is it just a legal decision or does politics come into it?

In the parliamentary answer Mr Straw gave on 22 October, he added: 'this will not be a political decision: I am exercising my statutory responsibilities'. On the other hand, if parliament has given a discretion to a politician it can hardly expect that politician to ignore political issues.

At the end of the extradition process Mr Straw has to decide whether someone whose extradition is sought should be sent to the country which wants to try him. On this issue, Lord Nicholls said: 'Arguments about the effect on this country's diplomatic relations with Chile if extradition were allowed to proceed, or with Spain if refused, are not matters for the court. These are, par excellence, political matters for consideration by the secretary of state in the exercise of his discretion under section 12 of the Extradition Act.'

Is it just the Spanish request that is being dealt with here - other countries have lodged similar charges?

The Spanish request is further advanced than the others. If others are received, no doubt they would be considered.

What happens if Mr Straw decides to proceed with extradition next week?

The will be a hearing at Bow Street court and perhaps further appeals. If the courts grant extradition, the home secretary will have the last word. Mr Straw can't send General Pinochet to Spain if the courts refuse to extradite him. But even if the courts allow extradition, Mr Straw can refuse to send him for trial in Spain.

How long could all this go on?