MPs will tomorrow vote on whether to endorse controversial prosecution guidelines on assisted suicide in England and Wales.
But critics say the guidelines have introduced uncertainty to a law that clearly makes assisted suicide illegal.
One MP, a qualified doctor, says assisted suicide is fraught with dangers because it involves decisions that are irreversible.
But another MP, who will lead tomorrow’s debate, said he was “sympathetic” and that the Commons should back the guidelines.
The prosecution guidelines mean that people are unlikely to be charged with assisted suicide if their actions were motivated by compassion.
The guidelines were published in February 2010 following a legal action by assisted suicide campaigner, Debbie Purdy.
The law on assisted suicide allows prosecutors to not pursue cases that are not in the “public interest”.
She has Multiple Sclerosis and wanted reassurance that her husband would not be charged with assisted suicide if he helped to kill her.
The courts ordered the Director of Public Prosecutions, Keir Starmer QC, to publish the circumstances that may determine whether a prosecution is in the “public interest”.
The resulting guidelines did not change the law, but critics said they diluted the law in the eyes of the public and were a step towards the legalisation of assisted suicide.
Tomorrow will be the first time MPs have debated assisted dying in the House of Commons since 1974.
Both the General Medical Council and British Medical Association are opposed to any change in the law, asserting that doctors do not want to legalise assisted dying.
Earlier this year the Archbishop of Canterbury also said weakening the law on assisted suicide would be a “disaster”.
Dr Rowan Williams made the comments at the Church of England’s General Synod meeting in London during a debate on a report chaired by Lord Falconer, which advocated assisted suicide.