A woman who helped her husband take his life has welcomed the first Commons debate on assisted suicide in 15 years.

MPs will vote on whether they agree with the Director of Public Prosecutions’ (DPP) policy during a full day debate at the House of Commons on March 27.

The DPP’s policy, laid out in 2010, sets out the factors for and against prosecution in cases of assisted suicide.

Susan McArthur, from Weybridge, helped her husband Duncan die at home, and said she was grateful they took a compassionate approach to her case and decided it was not in the public interest to prosecute.

Mr McArthur took his own life on October 30, 2009, with a glass of his favourite tipple, and his wife of 42 years holding his hand.

His death was illegal, however, because his wife had prepared the fatal dose Mr McArthur took.

Doctors diagnosed motor neurone disease and Mr McArthur had reached a stage where he no longer felt his life was acceptable.

Mrs McArthur said: “I think that Duncan’s major fear was the loss of control of his own destiny and within days of diagnoses and research on the inevitable consequences of the disease his decision was made, he declared emphatically that he was not prepared to see it out to the end and would therefore end his life at a time of his choosing.

“I was prepared to support him in whatever decision he made and he knew that I would always care and look after him if he changed his mind.”

The next two-and-a-half years were difficult, but his decision to end it all before he was unable to make that choice gave him some inner peace.

Mrs McArthur said: “The last two nights before he died he had the best nights’ sleep he had had in months, he was resigned, even cheerful.

“He was the best of men - brave, determined and incredibly courageous.”

Following his death, the family were put through the stress of a police investigation and a delayed funeral while they waited for toxicology results.

Fortunately there was no prosecution, but Mrs McArthur wants to see new processes for people to control their own fate and end their suffering.

Mrs McArthur said: “I was very lucky to have had him for as long as I did, he will always be in my heart.

“There has to be a better way for people like Duncan who are suffering from a terminal illness and are in possession of all their faculties.

“He made an informed decision; the great sadness is that he was unable to do this legally.”