The assisted dying private members bill, introduced in September by Nationals MP Trevor Khan, would have provided patients 25 years or older whose deaths were imminent and were in severe pain, a choice by which they could have ended their lives.

Safeguards included a requirement to consult two doctors, one a specialist in the illness, and a psychiatrist or psychologist.

The bill also contained a 48-hour cooling-off period, the right for a patient to rescind the decision at any time and for close relatives to challenge patient eligibility in the Supreme Court.

But it was defeated 20-19 after a marathon sitting in the senate that went late into the evening.

Dubbo MP Troy Grant had declared he would vote with the wishes of his electorate if the bill reached the lower house, saying he was “comfortable in my own mind that it doesn’t mean more people will die, it means less people will suffer”.

But the result of Thursday’s vote means the matter will not reach the lower house, where Premier Gladys Berejiklian and opposition leader Luke Foley were among its opponents.

“It was a close vote obviously, and the proponents of the bill are obviously disappointed,” Mr Grant said.

“It’s a tough issue. It’s divided the community in relation to their opinions, and the proponents and opponents made their cases very clear in their speeches.

“I won’t get a chance to vote because it won’t come to the lower house My survey in Dubbo showed just under 60 per cent in favour of the bill but it wasn’t about numbers, what I’m really grateful to the community for is the quality of the feedback.

“They told me in clear and unequivocal terms why they supported it and why they didn’t, and were able to give me a good understanding of where community sentiment was to help direct my vote if I was put in that position.”