The European Court of Human Rights is to rule on the whole-life sentences of three convicted British killers.
Jeremy Bamber, Peter Moore and Douglas Vinter claim that a sentence which condemns them to die in prison amounts to a breach of articles three, five and seven of the European Convention on Human Rights.
Their legal team has argued that all sentences should be periodically reviewed, and that any sentence where the prisoner's rehabilitation does not lead to review amounts to "inhumane or degrading treatment".
A whole-life sentence means a prisoner will be kept in prison until death with no prospect of parole.
In general, whole-life tariff prisoners' only hope of release is a decision by the Secretary of State on compassionate grounds, because of old age or ill health.
The government has argued strongly against any changes.
Ken Clarke, the Justice Secretary , said in February: "There will always be a small number of prisoners whose crimes are so appalling that judges rule they should never become eligible for parole.
"Their decisions should be upheld."
Jeremy Bamber was jailed for killing his father, mother, sister and her twin sons in 1985.
Peter Moore, dubbed the "man in black", was given a whole life sentence for mutilating and killing four men in the mid-nineties.
Douglas Vinter was convicted of stabbing and killing his wife - three years after being released from jail for another murder.
Even if the three are successful at the European Court of Human Rights it would not mean immediate release.
Legal commentator Joshua Rozenberg told Sky News: "These people are not going to be released any time soon.
"The most I think they can hope for is to have their sentence reviewed at some point in the future.
"On the other hand it does not follow that they are going to be released even if the case is reviewed in ten, twenty or thirty years' time if it is thought they could be a danger to the public.
"What this case will win for them is some prospect of hope if they are successful, but also quite a lot of public disquiet."
Islamist hardliner Abu Qatada will also hear today if his appeal to the European Court of Human Rights is successful.
The al Qaeda sympathiser, wanted on terrorism charges in a number of countries, is fighting an extradition order which would see him deported from the UK to his native Jordan.
Qatada argues that he is at risk of torture if returned to the Arab kingdom.