Dr Peter Saunders, from Care Not Killing, a UK based organisation which promotes care and opposes euthanasia said Paul Lamb is seeking a "very radical change in the law."
He said: "If he was successful in getting that legal change it would drive a coach and horses through not the suicide act but the murder act as well and that would put a lot of vulnerable, elderly people at risk
"The proper place to be making this decision is not in court, it's in Parliament", he added.
More top news
Fire services are spending thousands on the 25-stone models - nicknamed 'Barry' - to learn how to handle larger patients.
Ahmed Hassan, 18, has been charged with attempted murder and causing an explosion with intent to endanger life.
A growing number of rank and file officers say they support being routinely armed while on duty in the wake of terror attacks.