"His Majesty's judges are satisfied with the almost universal admiration in which they are held," noted Lord Hewart, the Lord Chief Justice, in 1936.

How today's judges must long for a world in which that could be said.

If any of them leafed through the Sun last week - admittedly, not the judiciary's favourite reading - they would have been confronted by a series of headlines that claimed to "name and shame 10 of the top judges guilty of being soft on killers, child sex beasts, rapists and other violent criminals".

The tabloid went on to "demand? that judges who hand down lenient sentences be sacked".

The catalyst for the outrage was the revelation that, over the past three years, Lord Goldsmith, the Attorney General, has referred more than 300 sentences to the Court of Appeal on the grounds that he thought they were "unduly lenient".

The Court of Appeal agreed with him and increased the sentence in two-thirds of those cases. In the rest, the sentence was left unchanged.

Although the Sun claimed that ministers supported its campaign, the reaction from the Government was in fact contradictory, with some ministers echoing the criticism and others defending judges.

Is there a serious problem of "soft judges" handing down "pathetic" sentences?

Dr David Thomas, a barrister and former professor of law at Cambridge University, who studies sentencing policy, thinks that there is not.

"In an average year, judges of the Crown Court pass sentences in between 70,000 and 80,000 cases. About 60 of those sentences are increased by the Court of Appeal on the grounds that they were 'unduly lenient'.

"Sixty cases out of 80,000 is less than one 10th of one per cent. That hardly represents a serious problem.

"Moreover," he adds, "many more sentences are decreased by the Court of Appeal on the grounds that they were 'excessively severe' than are increased because it is decided they were 'unduly lenient'.

"About 20 times as many, in fact. So if having your sentence changed by the Court of Appeal is the guide, the problem with our judges is not that they are too lenient: it is that they are too severe."

Judges also do not have much discretion in the length of sentence they can impose for any given offence.

The majority of the sentences that are increased by the Court of Appeal are only increased by one or two years, which does not suggest that the Appeal Court thought that the original sentence was "pathetic".

The case in which the Appeal Court more than doubled the judge's original sentence of 10 years to one of 23 years was unusual - and had a special explanation.

Luan Plakici had been found guilty of trafficking young girls to sell them into prostitution and sexual slavery. When Judge Robert Winstanley gave Plakici 10 years, the maximum sentence for the offence Plakici had committed was 14 years.

There were no further guidelines. The Court of Appeal decided that it was important to send a signal that trafficking in people was "despicable", so it decided to increase Plakici's sentence to 23 years, essentially by having his sentences run consecutively, rather than concurrently, as is usual.

"I don't think it was open to the original trial judge to impose a sentence of 23 years, or anything like it," avers Dr Thomas.

"There was nothing on the statute book, or in the sentencing guidelines or previous Court of Appeal decisions, that indicated it was permissible to do so."

The Government has been eager to reduce judicial discretion on sentencing to a minimum. The result has been a blizzard of legislation that has tried to fix sentences so that judges cannot vary the number of years a criminal spends in prison.

The results, however, have often been at odds with the principle that "the punishment should fit the crime".

As one High Court judge, speaking on condition of anonymity, told The Sunday Telegraph: "Justice requires that I impose a sentence on the basis of the facts I hear about the defendant at his trial.

"Almost all of the criticism of sentences comes from people who have no idea of what those facts are. They would almost certainly change their minds about the sentence if they had actually been in court."

Perhaps learning about "all the circumstances" would reconcile people to single-digit sentences for serial child abusers, for instance - but perhaps it wouldn't.

"The amount we must reduce a sentence for particular mitigating circumstances is all laid down in the sentencing guidelines and in the statutes," explains the judge.

"We have almost no discretion. In most cases, we cannot impose significantly higher sentences even if we want to. Very few of the sentences that strike the public as low for the crime of child abuse are increased significantly, or indeed at all, by the Court of Appeal."

Like most judges, this particular one resents the extent to which recent legislation tries to force him "to act like a slot machine, coming out with a fixed sentence for every crime, without any regard at all to the individual circumstances that define it".

Confusing and sometimes contradictory legislation has also made the judges' task harder. For instance, the Criminal and Justice Court Services Act of 2000 contained dozens of provisions affecting sentencing.

One of them required courts to send anyone found to be in breach of a community service order or of the terms of his probation straight to prison. It was on the statute book - but it was never enacted.

Three years later, that provision was repealed by the Criminal Justice Act, which contained a new set of rules for sentencing.

The Government has on occasion realised that its attempt to eliminate judicial discretion can backfire. The most famous example was when Labour introduced the "two strikes" law, passed by the Tories, under which a man convicted for a second "serious sexual or violent offence" had to be given a life sentence.

This led to a man being given a life sentence for robbing a shop with a banana: the fruit was used as an imitation firearm, and in the eyes of the law the robbery was therefore a "serious violent offence".

As the man already had a conviction for a violent robbery, the judge was forced to give him life.

The way the judges have found to get round the mandatory life sentence for a second serious offence is to impose a life sentence, but to stipulate that only a term of a few years, and sometimes only a few months, has to be served.

Many such sentences have been imposed. Few have been increased by the Court of Appeal.

"When people are outraged by sentences from judges," explains Dr Thomas, "what they are usually actually reacting to is not what the individual judge has done. They are expressing their outrage at the whole framework of sentencing as it exists in Britain today."

Whether that is too "soft" or "pathetic" is, of course, the subject of intense debate. "But, in criticising the judges for it," says Dr Thomas, "you're really just shooting the messenger.

"The responsibility for that framework lies with the Government. It doesn't lie with the judges - they just implement it."