An English woman with multiple sclerosis has won permission to bring a High Court challenge to clarify the country's law on assisted suicide.

Debbie Purdy, 45, went to court to discover whether her husband would be prosecuted if he helps her travel to a clinic in Belgium or Zurich, Switzerland, to commit suicide, if her condition becomes unbearably painful.

Two judges ruled that Purdy has the right to challenge the alleged refusal of the country's director of public prosecutions to set out a clear policy on whether people might be prosecuted if they help loved ones to die.

Purdy, who said she was "really pleased" about the ruling, wants to choose her own moment to die. Her condition, which she developed in 1995, has recently deteriorated and she is now in a wheelchair.

Click here to watch Purdy discuss her challenge.

Her fear is that her husband Omar Puente could be arrested on his return home from the clinic.

"Ninety-two Britons have gone to Switzerland for assisted suicide," she explained to Sky News.

"Although the law says that anybody who aids, abets, counsels or anyone who helps someone to commit suicide faces prosecution, only one person has been arrested." she said.

That meant the law was still unclear, she pointed out.

"I want the law clarified so that I can be sure my husband will not be arrested," she said, adding that she was not prepared to let that happen to him.

The judges ruled that "without wishing to give Ms. Purdy any optimism that her arguments will ultimately succeed," she did have an arguable case.

The director of public prosecutions, Sir Ken Macdonald, has so far indicated there is no specific policy for assisted suicide and he is not in a position to grant immunity from prosecution.

When asked about her health, Purdy said, "At the moment, I am extremely healthy but I cannot know how I will be in a few months. It is ridiculous that I am having to do what the doctors cannot do which is to guess what my condition is going to be."

The case will go before the court in October.

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