Disability rights campaigners are to ask the Court of Appeal to examine whether the Director of Public Prosecutions (DPP) acted lawfully in changing prosecution policy in cases of assisted dying.
Merv and Nikki Kenward, from Aston on Clun, Shropshire, are seeking permission to appeal against a High Court ruling handed down in December 2015.
Mrs Kenward was stricken by Guillain-Barre Syndrome in 1990 and left almost completely paralysed for five months, able only to blink her right eye.
The former theatre manager, who now uses a wheelchair, said that the High Court's decision was "bizarre" and "leaves vulnerable people at risk from dodgy doctors".
DPP Alison Saunders amended the prosecution policy for assisted suicide in October 2014.
Mr and Mrs Kenward, who are supported by the Christian Legal Centre, say that the change in wording makes it less likely that healthcare professionals will be prosecuted for assisting suicide.
"On behalf of the disabled, elderly, terminally ill and others who are vulnerable, we will continue the fight for a reversal of this deceptive and dangerous liberalisation of prosecution policy," Mrs Kenward said.
The application in London will be heard by Lord Justice Longmore and Lord Justice Kitchin.