I loved my father-in-law Jimmy very much. One of the hardest years of my life was watching him die of cancer. He was just 48. So young. I’m only four years older than Jimmy was when he died.

The agony etched on his face - increasing daily, hourly, sometimes every minute towards the end - remains vivid if I shut my eyes and remember. I still can hear his cries of pain, even through the fog of morphine.

Jimmy finally died after months of suffering, just weeks before I married the daughter he was devoted to; fate is cruel. Jimmy was an ex-soldier; he knew hardship, he was tough, but cancer - the monster - devoured him.

I struggle to remember a time when I didn’t believe that every human on the face of this planet has the right to decide when their time is up. Even as a child this seemed natural to me. Jimmy’s death solidified those beliefs. For me, the right to die is the last great human rights battle.

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It was Jimmy inside his body, nobody else. Not some priest or minister, not some politician. Just Jimmy, alone with his pain.

Aren’t we all alone at the end, even if family are around the bed, even if our hand is held? There’s nobody but you in that body, in that mind. Alone. With pain.

So nobody has the right to tell another consenting adult that they must continue living, even though to live is to endure crucifixion.

The historical Jesus died in an afternoon. Today, like every day, thousands of men and women - thousands of Jimmys - suffer their own personal passion, their own confrontation with mortality and unbearable pain, for month upon endless month. It’s torture, an inhumanity, a sentence worse than death.

When my time comes there’ll be nobody - no police officer, no doctor, no priest or minister, no politician - who will prevent me ending my life should my final days be wracked by disease and suffering. I’ve made arrangements. I know what to do.

As society stands now, should that horror visit me, I’ll have to endure it alone. I’ll have to experience the knives of pain and mortal terror, and take my life in a lonely room. To do otherwise - to have assistance from family - would be to risk the liberty of my loved ones.

How could I leave this world knowing I’d somehow compromised the people I love through the act of my death? For if anyone should help me die, it’s prison. What cruelty we inflict. And for what?

The Herald: Liberal Democrat MSP Liam McArthur promoting his Assisted Dying BillLiberal Democrat MSP Liam McArthur promoting his Assisted Dying Bill (Image: PA)

Perhaps, though, we’re finally nearing change. Legislation is slowly moving through the Scottish Parliament. Yet legislation only ever follows society’s shifting soul. Politicians fear to tread where society’s thoughts haven’t yet travelled. Polls are the politician’s weathervane.

Today, two-thirds of us support legalising assisted dying. Opinion crystallises. Yet often some dreadful, symbolic act is needed to propel change. What will it take? A monstrous sacrifice?

Perhaps, the horror of watching Esther Rantzen die a lonely death will be the catalyst. To my generation, she’s an almost mother-like figure. Indeed, she’s just a few years older than my own mother.

Generation X grew up with her. She created Childline to protect us when we were young. We all hold some love for her.

This isn’t to beatify her. She’s a flawed woman, just as we’re all flawed - and that’s the point, we’re all the same in death - but there’s certainly softness in my heart for Esther Rantzen.

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There’s a genuine pull of sadness when I think of her travelling alone to the Swiss Dignitas clinic - for that’s her plan, now cancer has her in its grip. Her family cannot travel with her. To do so, would be seen as assisting or encouraging suicide. That can lead to 14 years' imprisonment.

Prison. For loving someone; for being with them in their darkest moment, their last minutes. Such laws need burned from the statute books.

We need humanity in law. Liam McArthur’s assisted dying bill will soon be debated at Holyrood. His proposed bill is rigorously safeguarded: only terminally ill, mentally competent adults will be assisted with ending their life.

Two doctors must confirm the person is dying, mentally fit and there’s been no coercion. There’s a fortnight cooling-off period, allowing reflection on the decision. Drugs are delivered by a registered medic; the person must administer the medication themselves. Every assisted death is recorded.

It’s still a dark, awful process to envisage, but it has decency. It gives humans agency over their most intimate moment. It gives the dying the chance to have their hand held as they leave this world.

To me, it seems such change is prevented by organised religion. I’m no friend of religion. However, everyone of faith is fully entitled to their beliefs. What they’re not entitled to do is inflict their beliefs on me. I do not have to suffer - nobody should suffer - in this life because someone adheres to an unprovable myth.

Fewer than half of Britons believe in the concept of "god". In 1981, 75% were believers - though I wasn’t one, even aged 11. Faith has become a minority activity.

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I’ve no wish to force my beliefs on people of faith, however. They’re entitled to the same respect as I and others. So I suggest that the various religions opposing right to die legislation maintain their teachings from the pulpit: that it’s a sin to take your own life, even as you scream in agony.

However, keep your nose out of the law. Render unto Caesar, remember? Those who face death’s agonies and believe in such teachings should be wished as good an end as any can hope for. The rest of us should be allowed to take our fate fully into our own hands.

When that day comes - when finally we’ve agency over our deaths - we’ll look back in dread and shame on all the Jimmys and Esthers. In fact, the people of the future will look back on us now - the way we, perhaps, look back on our ancestors’ barbarities - and ask: “How did they ever do such a thing? Why did they force each other to die in such agony?”