Media playback is unsupported on your device Media caption Paul Lamb: "I don't want people's sympathy - I want people's help"

Campaigners for the right to die are to have their arguments heard by the Supreme Court in the latest round of their legal battle.

It involves family of the late Tony Nicklinson of Wilts, who had locked-in syndrome, and Paul Lamb of Leeds, who was paralysed in a road crash.

They want the law changed so they can be allowed to die with the help of a doctor.

Judgement is likely to be issued at a later date.

The court will have to decide if the law prohibiting assisted suicide is incompatible with the European Convention on Human Rights by denying Mr Lamb, and others like him, the right to choose the timing of their death.

Analysis These cases raise some of the most profound ethical, moral and legal questions imaginable. Whilst it is not a crime to commit suicide, it remains a serious crime to assist someone to do so, punishable by up to 14 years imprisonment. Paul Lamb's argument is that the current law represents a disproportionate and discriminatory interference with his right to a private and family life under Article 8 of the Human Rights Act, because it does not allow him to end his life at a time and in a manner of his choosing - with the help of a medical professional. To fix that, he wants there to be a defence available to any doctor who assists a severely disabled person to end their life. This would be subject to strict safeguards, and would have to be sanctioned by a court in each individual case. However, the defence is known as 'necessity' and it is based on the idea that it is necessary to assist to end a life in order to end unbearable suffering. That is hugely controversial and whilst many people will have enormous empathy with Paul Lamb and others like him, they fear that any relaxation in the law governing assisted suicide or euthanasia, would expose vulnerable groups such as the elderly, those with dementia and the disabled to pressure to end their lives so as not to be a financial or emotional burden.

There will be nine judges on the panel, rather than the normal five, overseeing the four-day hearing.

'Unanimously dismissed'

Paul Lamb, 57, has been almost completely paralysed from the neck down since a car accident 23 years ago and says he is in constant pain.

He has called for the law to be changed so any doctor who helped him die would have a defence against the charge of murder.

Tony Nicklinson was paralysed from the neck down after suffering a stroke while on a business trip to Athens in 2005.

After losing his High Court battle last year, he refused food and died naturally, aged 58, a week later at his home in Wiltshire. His widow Jane is continuing his fight.

Earlier this year, Mr Lamb joined forces with Mr Nicklinson's family to fight a joint legal battle.

'Conscience of the nation'

In their Appeal Court case, the decision centred on whether the High Court was right to rule Parliament, not judges, should decide whether the law on assisted dying should change.

The three Court of Appeal judges unanimously dismissed the Nicklinson and Lamb challenge.

Media playback is unsupported on your device Media caption Jane Nicklinson: I don't want other people to suffer like my husband

In the judgement, the Lord Chief Justice Lord Judge said Parliament represented "the conscience of the nation" when it came to addressing life and death issues, such as abortions and the death penalty.

"Judges, however eminent, do not: our responsibility is to discover the relevant legal principles, and apply the law as we find it," he said.

At the same hearing a third paralysed man won his case seeking clearer prosecution guidance from the director of public prosecutions (DPP) for health workers who help others die.

The man, known only as Martin, wants it to be lawful for a doctor or nurse to help him travel abroad to die with the help of a suicide organisation in Switzerland. His wife and other family want no involvement in his suicide.

The Supreme Court will also deal with the DPP's appeal against the Court of Appeal's ruling in Martin's favour.