The single offence of murder should be replaced by "degrees of homicide" in England and Wales, the director of public prosecutions says.
Ken Macdonald QC calls for three or four "degrees of homicide"
Ken Macdonald QC told the Times those convicted of lesser degree murders could receive less than a life term.
Judges complain current laws force them to treat convictions, say for serial or 'mercy' killings, in the same way.
Some offenders were also going free as prosecutors faced an "either/or" case of manslaughter or murder, the QC said.
A Home Office spokeswoman said there would be "no compromise on a mandatory life sentence for murder".
She said the government remained committed to a review of murder laws promised last October by then-Home Secretary David Blunkett.
This followed a report in August by the independent Law Commission that branded legislation on murder "a mess".
"For over 500 years, the definition of murder, and many of the defences to it, have been developed in fits and starts by judges in individual cases," said the Law Commission's criminal law commissioner, Dr Jeremy Horder.
"There has been little legislative reform. In consequence, the law lacks coherence."
Mr Macdonald, in charge of prosecutions in England and Wales, said currently prosecutors hoping to win a conviction had to either charge a suspect with murder, or the lesser charge of manslaughter.
Opting for the more serious charge ran a greater risk of losing the case - which could mean guilty defendants going free, he said.
Mr Macdonald told the Times: "There should be degrees of homicide, not just murder or manslaughter, but three or four degrees."
"If we are talking about a serious homicide killing with an intention to kill, that should attract a mandatory life sentence," he said.
The Home Office spokeswoman said: "We are still committed to the murder review, an announcement of its terms of reference will be made in due course.
"Whatever happens there will be no compromise on a mandatory life sentence for murder."
The Daily Telegraph's legal affairs correspondent Joshua Rozenberg said the government would be wary of going down this road.
"On the other hand if it could be shown that people are simply walking free, as Ken Macdonald is worried about, then I think they would have to recognise that the law needs to reform," he said.
The Law Society for England and Wales also welcomed a review of the current law.
A spokeswoman said: "Clearly if offenders are slipping through the net we need a more flexible approach which enables judicial discretion."
Rather than tying the legal system further in knots, what we need is a sliding scale for sentencing of individuals convicted of murder. Do away with a meaningless "life" sentence and have no upper limit on tariff so that someone who intends to kill their victim can be sentenced to (e.g.) 99 years in jail - a true life sentence. The sentence could be determined by a sentencing panel made up of a judge and members of the public (or even the jury?) - that way the sentence would fit the crime.
Dave, Moira, N. Ireland
Our justice system is not just a means of punishment, but also is (or should be) a means of rehabilitation. A person sentenced to murder is allowed out of prison after 15 years, or whatever, having been judged to have been both punished and rehabilitated. Hopefully they will be able to be a valuable member of society again. If not they are actually under a system called "life parole" for the rest of their life. This means they are monitored closely by parole officers and can be put back in prison with no trial anytime.
Chris Wilson, Brighton, UK
A life sentence does not mean life. I believe only 28 people are currently serving real life sentences (i.e. they will die in jail). In effect being sentenced to "life" usually means about 15 years. If nothing else we need a reform of the sentencing laws to prevent people like Peter Sutcliffe challenging the legality of his sentence. If we introduce a crime of Murder One with a mandatory whole life tariff for especially evil crimes it removes a legal loophole.
I think that a sensible system of justice is long overdue. If a convicted murderer is given a "Life" sentence, this should mean the rest of their natural life, not 10 years! If someone kills while driving under the influence of drugs or alcohol then that too should be treated as murder! It is still the taking of life. If the law operates in a common sense and transparent way it will gain the respect of the country. At the moment it is abused by those with a clever barrister, and often fails to protect the innocent.
Paul, Cambridge, UK
The sentencing that is in place at the moment simply doesn't work. It needs to go back to the drawing board. Longer sentences for pre-meditated murder, shorter for mercy killings, with the manslaughter charge scrapped.
Matt Mosley, Heanor, Derbyshire
The law needs to be changed - though I suspect it will only lead to murderers getting even lighter sentences than they do now. Better still would be to overhaul the entire legal system in this country, inject it with some common sense, and give more consideration to victims of crime.
Obviously there are different circumstances in every crime - not just murder. I don't think we need to further legislate and burden an already archaic legal system, when the simple answer is to ensure that judges are the right people for the job. If the government must make changes to the law surely it should be in the sentencing of criminals
Randell, Bridgend, UK
All this review will accomplish is further lining the pockets of solicitors and barristers as they haggle over which 'degree' of murder is applicable, adding days and weeks to the duration of a case. The only reform necessary is to afford the presiding judge greater discretion in sentencing.
Dan, London, UK
In my view, murder is a black or white thing - either you murdered them or you didn't. There is no such thing as "Degrees of murder". It's ridiculous. Obviously, "Mitigating Circumstances" should be taken into account when passing sentence, but that happens already!
Matt Jenkins, Bristol, UK
As a law student, I have become increasingly frustrated by the needlessly complex and inflexible law on homicide. In its arrogant rigidity, it fails to appropriately deal with the fundamentally different cases of the terrorist who intends public exposure but not death, and the husband who eases his wife's suffering by aiding her death. In this respect the current law is both over - and under - inclusive.
Kieran Chadha, Cambridge
I think that it would be a sensible idea to create a distinction between various types of killing. However, it would make even more sense to stop using the term 'life' to describe 20 years imprisonment - clearly this is NOT a lifetime. A murderer should be sentenced to a proper 'life' term.
Sean, London, England
No, there should be no change to the current law. Murder is murder, and as such should continue to merit a life sentence. There is always the alternative of lesser charges such as manslaughter.
Paul Phillips, Birmingham UK
It is quite obvious that sentences need to match the crime. If you a wife and have been repeatedly beaten by your husband and the on one of these occasions the wife strikes out in defence and accidentally kills her husband cannot be treated the same as a serial rapist or murderer. Common sense must prevail in these situations.
Robert Taylor, Chichester
This strikes me as an unnecessary solution to an unnecessary problem caused by tabloid government and their insistence of imposing statutory sentencing policy on judges in response to red-top outrage.
Malcolm McMahon, York, UK
The reason the mandatory sentence was introduced was because of judges making terrible decisions and letting killers free after just a few years. If we changed it back the same bad decisions would be made again.
Andrew, Ascot, UK
Time and again we see this sort of thing being brought up - " we should legislate for this that and the other..." Judges are so called because they are carefully selected for their 'judgement'. We are increasingly denying them that judgement by restricting their actions. It is about time we stopped getting so carried away with new laws and 'the letter of the law' and moved to a more sensible system where a judge decides the severity of a crime and its appropriate punishment.
Dave, Suffolk UK
I agree that the law should be changed. Whilst murder is the gravest of offences, and is perhaps unique in its effect on society, Judges should have discretion with regards to sentencing. It is wrong that all murders are dealt with in the same manner.
Luke Milburn, East Grinstead, England
I think a change in the way murder cases are tried is long overdue, after all behind every murder trial is a human tragedy, obviously for the victim but also quite often for the perpetrator. So perhaps with a change in the law each case can be tried with a little common sense and compassion which should lead to more accurate verdicts and appropriate sentencing.
Dominic, Clevedon, North Somerset
Euthanasia should be decriminalised. Well controlled but legal. This would take it out of this argument altogether. The word 'murder' should not be used at all in circumstances that involve relieving a loved-one of suffering.
Neil, Oxford, UK
I think it's only sensible - murderers come by degrees the same as everything else in life - serial murderers are not the same as someone who helps their terminally ill and agonised loved one die, and all are different from the battered spouse who one day batters a bit too hard back. Surely it is only common sense that judges have the power to treat all these acts as crimes, as they surely are, but of differing severity.
Ellie, Edinburgh, UK
There has already been compromise on the mandatory life sentence for murder; life used to mean life not 15 years or whatever the judge decides on, on that particular day. But before we start to rewrite the law books again we should make sure our laws that we already have are carried out by the judges in a way that means justice.
Mrs A Wilson, Chichester Sussex
As an Oxford law undergraduate I have studied the criminal law of England & Wales in some depth. The law relating to murder in this country is indeed a mess and some serious reforms are urgently required. The present mandatory life sentence for murder does not give the judiciary the flexibility they need in passing down a sentence reflective of the intricacies involved in each case.
Adam, Oxford, UK
There isn't much point in changing the murder law. Ok I agree that serial killers should be dealt with more harshly than other murderers but they already are. Myra Hindley died in prison. Judges already have the power to hand out multiple life sentences anyway.
Daniel Meadowcroft, Stockport, England
I think it is an intelligent decision for judges to make merit-based decisions on the circumstances behind murder. After all, a gang killing hardly merits the same treatment as euthanasia. I'm sure the Daily Mail readers will disagree though.
Pete, Southampton, UK