Suppose you had encountered Neil and Kazumi Puttick last Sunday evening, as they approached the edge of Beachy Head. Suppose, further, that you had somehow intuited that they were about to leap into the 500ft drop near the Belle Tout lighthouse. Would you have done everything in your power to dissuade them from taking that plunge into certain annihilation?

Imagine, then, that 34-year-old Neil and his 44-year-old wife Kazumi explained to you that they were carrying in their rucksack the body of their profoundly disabled five-year-old son Sam, who had died at their home in Wiltshire two days earlier; that they had made this long journey to the edge of England because they had always felt that their life without Sam would be intolerable; that they were indeed now suffering unbearably and that all they wanted to do was to join him in the hereafter.

Would you, at that point, rush off to get members of the Beachy Head chaplaincy team to help prevent the Putticks from ending it all? Or would you tell them that it was no one’s right to question their decision or the reasons for it; that, in fact, you knew the best spot to leap off to avoid any possibility of landing safely on a ledge and would be happy to lead them to it?

To judge from the responses to Lord Falconer’s article last week, advocating the removal of any possibility of prosecution against those escorting would-be suicides to the Dignitas clinic in Switzerland, the great majority are in the second category.

On the other hand, campaigners for euthanasia are formidably persistent and well organised; so members of the “go ahead and jump” lobby - as we can call it in this circumstance - might also have been their usual busy selves in drumming up e-mails of support for Falconer’s opinion.

Charlie Falconer, in fact, is the author not just of a newspaper article, but also of an amendment to the Coroners and Justice Bill due to be put to a vote in the Lords later this month. That bill is designed to bring the law to bear on the sinister spread of websites encouraging people to kill themselves - in that sense it is a measure designed to add greater legal protection for those vulnerable to such insidious suggestions.

Yet Falconer and his supporters want this bill also to include an amendment which would remove all threat of legal prosecution from: anyone “encouraging or assisting the suicide or attempted suicide of another adult if a) the act is done solely or principally for the purpose of enabling or assisting [someone] to travel to a country or territory in which assisted dying is lawful; [and] b) prior to the act two medically registered practitioners, independent of each other, have certified that they are of the opinion in good faith that [the person] is terminally ill and has the capacity to make [a] declaration”.

Falconer’s proposal limits its applicability to the “terminally ill”, presumably to avoid the accusation that members of the public could whisk off to Dignitas compliant relatives whose death was not imminent, without any fear of legal consequences. Yet in his article - soothingly entitled “A more civilised approach to suicide” - the solitary case he cites in favour of his amendment is an “assisted suicide” of someone who was not terminally ill: that of Daniel James, a 23-year-old rugby player who had been paralysed in a collapsed scrum. Mr James had been regaining some feeling in his fingers at the time of his one-way trip to Switzerland and he was at all times able to breathe without any artificial assistance.

It is, to say the least, odd that Falconer should publicly single out as a beneficiary of his proposal a family whose case would not qualify. A cynic might suggest that this is a revealing slip, showing that he is already anticipating the inevitable next stage of the euthanasiasts’ campaign once this amendment is accepted.

In fact, this so-called “slippery slope” is an entirely logical application of the fundamental argument for legalising voluntary euthanasia. It is based on the assertion that a person’s life is entirely his own and that if he wants to do away with it, but lacks the physical or mental power to carry out an act of self-extermination, then it should be an absolute right to hire someone else to kill him. Whether or not such a person is terminally ill - and this is in any case a difficult prognosis to guarantee with absolute certainty - is irrelevant to the argument.

The advocates of “assisted suicide” generally use the phrase “unbearable suffering” as their justification for voluntary euthanasia - or even, analogous to the way in which infirm household pets are treated, involuntary euthanasia. Yet there is no physiological definition of “unbearable suffering”.

After all, Sam Puttick had been much more severely incapacitated than Dan James. The little boy had, since a car accident in 2005, been completely paralysed from the neck down, unable even to breathe unaided; but as a neighbour of the Putticks told the press: “Sam never complained, he was always happy and full of smiles.” It was Sam Puttick’s parents who were truly in a state of unbearable suffering once he had died.

A great virtue of the law as it stands is partly that it seeks to protect the interests of the most vulnerable and not just the interests of those strong-willed people who are utterly determined on an “assisted suicide” (as the European Court of Human Rights observed in its landmark 2002 judgment, Pretty vs The United Kingdom). It also has the benefit of clarity: it attempts no nice distinctions between one state of mind or another, or defining what is really meant by a “terminal illness”.

It is true that the director of public prosecutions has chosen not to bring charges against any of the hundred or so British families who have used Dignitas to date: as with any law that might have been broken, the DPP has the absolute discretion not to bring a prosecution if it thinks action would not be “in the public interest” - or that a jury would be unlikely to convict.

Clearly the DPP feels that no case has yet arisen which meets those standards; but the law still stands as a deterrent to those who would exploit a vulnerable relative for financial or other reasons.

Falconer tells us that the parents of Dan James were “extremely distressed” by the fact that they were interviewed by the police about the circumstances of their son’s death before the decision was taken not to prosecute.

Yet surely it must have occurred to a former lord chancellor that even after such a change in the law as he proposes, the police would still be obliged to interview anyone who had assisted in procuring someone else’s death. Indeed, we would want it to be so. Falconer’s initial “two doctors” safeguard sounds impressive, but let’s not forget that every cremation certificate signed by the late Dr Shipman had been willingly countersigned by a second GP.

Falconer ended his article by declaring that “if this amendment is passed it should be called the Purdy amendment”. Debbie Purdy is the woman with multiple sclerosis who has been challenging the existing law on “assisted suicide”.

Attractively modest though this may appear on the part of Charlie Falconer, I don’t think he should be allowed to get away with it. The amendment is so potentially dangerous that his name should be attached to it in perpetuity - just in case anyone forgets whom to blame when its shortcomings are ultimately revealed in the courts.

dominic.lawson@sunday-times.co.uk

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