No-one could fail to be moved by Gordon Ross's courageous and dignified decision to face the prospect of his own death head on and pursue in court the right to have help to die.

Mr Ross lives with a combination of health problems, including the degenerative disease Parkinson's. Over time, he has lost the capacity to engage in activities others take for granted, from driving to walking. Ending his life, he says, is "very low down my list of priorities if it is there at all", but he understandably wishes to know that, should the time come when he feels he no longer wants to go on, that he can ask for help to die without the person who assisted him becoming a criminal in the eyes of the law.

Coming three months after independent MSP Margo MacDonald relaunched a revised version of her assisted suicide bill in the Scottish Parliament, this case makes clear that the status quo is coming under increasing pressure. The question of whether anyone should have the right to help another to die is a painfully challenging one, ethically and legally, but it is not going to go away, especially not given the ageing population and the growing numbers of older people in Scotland with degenerative conditions who are actively engaging in the debate. The latest poll on the issue shows that a clear majority of Scots - 69% - support Ms MacDonald's bill.

Mr Ross believes that the law as it stands undermines his human rights. This echoes arguments in the case, currently before the Supreme Court, of Paul Lamb and Jane Nicklinson, the widow of Tony Nicklinson. Mr Lamb is almost completely paralysed and Mr Nicklinson, who died in August 2012, had locked-in syndrome; their lawyers are arguing that the prohibition on assisted suicide is incompatible with the European Convention on Human Rights.

Their arguments have so far been rejected by the High Court and the Appeal Court, and the Supreme Court's ruling is due at any time.

The case highlights the way in which the right to die is perceived as a human right in itself. The notion of prosecuting someone for helping their loved one to carry out their wish to die is increasingly out of step with public opinion. That is why it is high time the Crown Office issued guidance, as the Director of Public Prosecutions (DPP) has done for England and Wales, on how those who assist with suicides should be treated. The DPP has made clear that prosecution is unlikely if the individual can prove that they acted on compassionate grounds and in accordance with their loved one's clear wishes. Mr Ross's lawyers want clarification on this very point in Scots law. The Crown Office should issue guidance without delay.

On the difficult question of whether or not to fully legalise assisted suicide, however, parliament should be the final arbiter. Ms MacDonald's bill improves on its earlier version by introducing plans for a trained facilitator to help an individual to die. Yet there must be stringent safeguards to ensure that someone who requests help to die is doing so voluntarily and not under pressure from friends or relatives, or out of fear they are becoming a burden. Whether a two-week cooling off period and having two medical professionals agree are sufficient safeguards is debateable. There are also serious concerns about how the parameters might be widened in future to allow assisted suicide in increasingly inappropriate circumstances.

If someone is terminally ill or has a degenerative disease and life has become intolerable to them, assisted suicide could be an act of great compassion, but the law must only be changed if unassailable safeguards can be put in place to protect the vulnerable.