Bradford multiple sclerosis sufferer Debbie Purdy has branded criticism of changes to assisted suicide laws as “scaremongering”.

Baroness Butler-Sloss, the former head of the family division of the High Court, Lord Mackay of Clashfern, a former Lord Chancellor, and Lord Carlile of Berriew, the Government’s terrorism legislation adviser, are among those who have formed a coalition which says the changes pose “serious dangers for public safety”.

A national newspaper reported that the group feared increasing numbers of elderly and infirm people would be pressurised into killing themselves under plans put forward by Director of Public Prosecutions (DPP) Keir Starmer.

The DPP held a consultation that says relatives will not be prosecuted as long as they do not “encourage” suicide and assist only a “clear and settled intention” to die.

The newspaper said the group believe the guidance is “not fit for purpose”.

The DPP guidance came after the Law Lords backed multiple sclerosis sufferer Debbie Purdy’s call for a statement on whether people who help someone commit suicide should be prosecuted.

Miss Purdy, of Undercliffe, Bradford, wanted to know what would happen to her Cuban husband, Omar Puente, if he helped her travel abroad to end her life.

She took her case to the highest court in the country after the High Court and Court of Appeal held that it was for Parliament, not the courts, to change the law. The Law Lords agreed that changes were a matter for Parliament but upheld Miss Purdy’s claim that the DPP should put in writing the factors he regarded as relevant in deciding whether or not to prosecute.

Miss Purdy, 46, said: “Are they suggesting that people who have an incurable condition, who do not see any possibility of their lives improving, should suffer in order to cleanse their consciences? It is unreasonable.

“The law could maybe save people’s lives if they wait until the absolute last minute to commit suicide. Our politicians can find the time to discuss their expenses, why can’t they find the time to discuss seriously prolonging the lives of British people?”

Dismissing the claims that elderly people would feel pressurised she said: “Old age is not an incurable illness, it is a stage of life. The elderly are not at risk, the group is missing the point and scaremongering.”