A third attempt is being made to pass legislation on assisted suicide in Scotland.

Liberal Democrat MP Liam McArthur is putting forward proposals for a Members Bill at Holyrood which, if passed, would permit assisted dying for adults who are both terminally ill and mentally competent.

Almost nine out 10 Scots (87%) are said to support the introduction of such legislation, Mr McArthur said, though a previous bid to change the law at Holyrood was voted down by 82 votes to 36 in 2015.

A cross party group of a dozen MSPs have already signalled their support for Mr McArthur’s bid to “introduce safe and compassionate assisted dying laws in Scotland”.

The group, which includes former Scottish Conservative leader Jackson Carlaw, as well as Green co-leaders Patrick Harvie and Lorna Slater, argued Scotland needed to change its laws so that those who are terminally ill can “be assured of dignified death”.

In an open letter, the MSPs said they had come together to work on the new Bill, as they argued: “The current law does not work and should be replaced with a safe and compassionate new law that gives dying people the rights they need to have a good death at a time that is right for them.

“We know there is a problem and it is incumbent upon us to provide a solution.”

Mr McArthur’s proposed Assisted Dying Scotland Bill, which is being supported by Dignity In Dying Scotland, Friends At The End and the Humanist Society Scotland, is being lodged at Holyrood on Monday.

It seeks to legalise assisted dying as a choice for adults who are both terminally ill and mentally competent, with a consultation planned for the autumn.

Mr McArthur said: “I  have long believed that dying Scots should be able to access safe and compassionate assisted dying if they choose, rather than endure a prolonged and painful death.

“The current blanket ban on such assistance is unjust and causes needless suffering for so many dying people and their families across Scotland.

“If you have reached the limits of palliative care and face a bad death, none of the current options available to you in Scotland represents an acceptable alternative to a peaceful, dignified death at home.”

Independent MSP Margo MacDonald made two attempts to pass legislation on assisted suicide (David Cheskin/PA)

The MSP continued: “The proposal I am presenting is one that co-exists with more and better palliative care and applies only to terminally ill, mentally competent adults.

“It has strong safeguards that put transparency, protection and compassion at its core and is modelled on legislation that has passed rigorous testing in other countries around the world.

“It is a proposal that chimes with powers our Parliament has to deliver change that helps build a fairer and more progressive society.

“Emerging from the pandemic, we have an opportunity to take the actions required to make sure that the end of our lives is more compassionate, fairer and more reflective of a dying person’s choice.

“We have the ability to create a new standard for how we die.”

Holyrood previously rejected previous bids to introduce assisted suicide in 2010 and 2015.

Both those Bills were brought forward by independent MSP Margo MacDonald, with Mr Harvie taking forward the second Bill following her death from Parkinson’s disease in 2014.

Michael Veitch, the parliamentary officer at the charity Care For Scotland, is against the Bill, claiming it would devalue the lives of disabled people and the vulnerable.

“This law will not just affect the small number of individuals who might choose to access assisted suicide.

“It will affect every person living with a terminal illness, fundamentally alter the doctor-patient relationship, devalue disabled people’s lives, and undermine wide efforts to prevent suicide,” he said.

“There can be no adequate safeguards.

“Providing a terminal prognosis is fraught with uncertainty.

“Vulnerable patients can be coerced.

“And the experience of other jurisdictions shows that an incremental extension of the law is inevitable.”

Speaking on the BBC’s Sunday Show, Mr McArthur said: “I would refute that and refute it very robustly.

“I would urge this organisation and indeed anybody with concerns about this Bill to look at the detail of the Bill that comes forward, to look at the details of the consultation and subsequently the Bill.

“This is not about assisted suicide, this is not about those who want to die.

“This is about giving those who have a terminal illness, who have been given a terminal diagnosis the opportunity, the choice for a more compassionate and dignified death.”