Sentencing for convicted murderers varies widely
When the Law Commission described the law on murder in England and Wales as "a mess" in 2004, it was reflecting the views of many judges, lawyers, police officers and others.
But, for politicians, tampering with the legislation has always been a hot potato.
For that reason, the government's homicide review, set up by the former home secretary, David Blunkett, last autumn, is not expected to produce speedy results.
And whatever it recommends, there is no sign that this government is prepared to scrap the mandatory life sentence for murder.
The anomalies in the homicide laws are legion.
In a series of cases, the higher courts have formulated a test which says murder is committed when the defendant unlawfully kills the victim in circumstances where he intends either to kill or cause grievous bodily harm.
Critics say this means a defendant who plants a bomb in a shopping centre and phones a warning, might escape a murder conviction if a shopper, who does not hear the warning, is killed.
Not so in Scotland, where someone acting with "wicked recklessness" can be found guilty of murder even where the intention to kill has not been proved.
In other common law jurisdictions, there are variations. In the United States, for example, some states require an intention to be established, others do not.
This is how the concepts of degrees of murder grew up.
The issue which has led to the re-examination of the law on murder is provocation.
This so-called "partial defence" has led to much soul-searching.
Men who kill their wives or partners in a fit of jealousy have successfully pleaded provocation to reduce a murder charge to manslaughter.
Whereas, a woman who kills her partner wilfully after years of abuse may be convicted of murder.
Men who kill their wives in a fit of jealousy can claim provocation
The former solicitor-general, Harriet Harman, was anxious to amend the law on provocation last year but failed to persuade the home secretary.
Like a house of cards, removing one part of the law on murder would cause the whole edifice to totter. Hence the wide-ranging review.
The mandatory sentence for murder was regarded as a quid pro quo for the abolition of the death penalty in 1965.
Successive home secretaries have maintained that the public expects murder to attract a life sentence.
But research for the Law Commission suggests that this popular mandate may no longer exist.
And even if it does, people are deeply confused about what constitutes murder in the eyes of the law.
The fact that there are huge discrepancies in sentences, depending on the success or failure of a plea of provocation or diminished responsibility, also undermines public confidence. And that will concern ministers.