A woman suffering from primary progressive multiple sclerosis hailed a ruling from senior judges today which appeared to clarify the law on assisted suicide.

Senior judges headed by the Lord Chief Justice indicated that they would act as a backstop and throw out any unjustified prosecution.

Debbie Purdy, who wants to know if her husband would be prosecuted if he helped her to go abroad to commit suicide, had gone to the Court of Appeal to have the law clarified.

Ms Purdy, 45, wanted to know the circumstances in which her husband, the Cuban violinist Omar Puente, would be liable to prosecution if he helped her to travel abroad to die in a country where the practice is legal.

In England and Wales, aiding and abetting suicide is a criminal offence punishable by up to 14 years in prison.

In his ruling today, the Lord Chief Justice noted that here are “broad circumstances” in which a prosecution will not be mounted – and even if one was, and a person was convicted, the courts had powers not to impose any penalty.

His comments, coupled with a recent detailed explanation by the Director of Public Prosecutions as to why he was not prosecuting the parents of the paralysed rugby player Daniel James, are the nearest to a statement of policy likely to be given by the courts and prosecuting authorities.

Lord Judge, and two other appeal judges, ruled that Ms Purdy, from Undercliffe, Bradford, West Yorkshire, was not legally entitled to the kind of specific guidance she was seeking.

The judges said: “Not withstanding our sympathy for the dreadful predicament in which Ms Purdy and Mr Puente find themselves, this appeal must be dismissed.”

Lord Judge added, however, that although the Director of Public Prosecutions had absolute discretion on a prosecution, the court had power to impose “no penal sanction” if it thought that appropriate.

The court could then “order that the offender should be discharged”, he added, and “might well question publicly the decision to prosecute”.

Britain’s most senior judge added: “In other words, the court is power of the protective system which discourages and would prevent or extinguish the effect of any arbitrary or unprincipled exercise by the DPP of his responsibilities. “

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