'Slippery slope' arguments Echoes of 1960s abortion debate

"It is entirely possible that future generations will puzzle over how such a fundamental right could ever be denied to them." These are the words of David Steel, the former leader of the Liberal party and a Westminster MP for more than three decades, referring to this Friday's historic vote in parliament on whether to legalise assisted dying.

- Harriet Sherwood

But Steel could just as well have been referring to a private member's bill he brought before parliament 57 years ago that was also about the right to bodily autonomy and was the subject of fierce debate and vocal opposition from church leaders.

That bill - passed under a free vote by MPs - became the 1967 Abortion Act, the "landmark legislation that underpins women's and girls' right to safe abortion services nearly six decades on", as Steel wrote in the Sunday Times.

One of the arguments deployed by its opponents was that it would be a "slippery slope"; that its strict criteria would be widened to allow "abortion on demand" up to a pregnancy's full term.

The argument is also being used by opponents of assisted dying. But fears raised in relation to abortion have not been realised.