Relatives who assist suicide can escape prosecution under certain conditions, the UK government has can escape prosecution, UK government has ruled.
Those who do not maliciously encourage others to die but assist only a ''clear settled and informed wish'' to commit suicide, will be spared, as per new guidelines issued.
Keir Starmer, the Director of Public Prosecutions said the guidance would make it easier for those helping someone commit assisted suicide to know if they will face prosecution.
However, more than 100 Britons with terminal or incurable illnesses have gone to the Swiss centre Dignitas to die and none of the relatives and friends involved in the cases has been prosecuted.
This is because the authorities have the power to use their discretion under the terms of the act.
The new move comes after the Law Lords backed multiple sclerosis sufferer Debbie Purdy's call for a policy statement on whether people who help someone commit suicide should be prosecuted.
In July, Law Lords ruled she had the right to know under what circumstances her husband would be prosecuted if he helped her travel abroad to die.
Mr Starmer said he hoped his guidance would now bring greater clarity to the issue, although he added all cases would still be investigated by the police.
He noted: ''There are no guarantees against prosecution and it is my job to ensure that the most vulnerable people are protected while at the same time giving enough information to those people like Mrs Purdy who want to be able to make informed decisions about what actions they may choose to take.''
He added: ''Assisting suicide has been a criminal offence for nearly 50 years and my interim policy does nothing to change that.''
Mr Starmer outlined 16 public interest factors in favour of prosecution and 13 factors against prosecution.
Some factors in favour of prosecution included that the victim was under 18 and did not ask personally on his or her own initiative for the assistance of the suspect.
Another factor in favour of prosecution was that a relative "persuaded, pressured or maliciously encouraged the victim to commit suicide".
Factors against prosecution included that the victim had a "clear, settled and informed wish to commit suicide" and that the victim "indicated unequivocally to the suspect that he or she wished to commit suicide".
Asked if the guidelines would result in an increase in people committing assisted suicide, he replied: "Only time will tell. It may do, it may not do."
He said: "Each case must be considered on its own facts and its own merits.
"Prosecutors must decide the importance of each public interest factor in the circumstances of each case and go on to make an overall assessment.
"I also want to make it perfectly clear that this policy does not in any way permit euthanasia.
"The taking of life by another person is murder or manslaughter, which are among the most serious criminal offences."
Asked if the policy would see an end to Britons travelling to clinics such as Dignitas, Mr Starmer said: "This policy applies to any act in England and Wales. It is not a policy designed only to cover those that travel abroad."
Ms. Purdy welcomed the move, saying it was important to underline that people considering suicide had a duty first to carefully consider all possible options.
"People will know what they must make sure of before they assist, and hopefully that will give people confidence not to make such a decision until the last possible minute."
Sarah Wootton, chief executive of the Dignity in Dying campaign group, agreed, saying the guidance represented a "significant breakthrough".
The Roman Catholic Archbishop of Cardiff, the Most Rev Peter Smith, said the Catholic bishops of England and Wales would be studying the draft guidance very carefully.
He said: "The comments made by the DPP in his article in the Daily Telegraph this morning provide helpful reassurance on two key points.
"First, he emphasises that the law has not changed - assisted suicide remains a criminal offence and the prosecution authorities have a duty to investigate each case.
"Second, he made clear that no-one can expect a guarantee of immunity from prosecution. These are important and necessary clarifications.
"What the DPP has been asked to do by the House of Lords is to give more specific guidance about the factors he will take into account in deciding whether or not to consent to a prosecution.
"I would not be seeking to argue that every criminal case should be prosecuted - there can indeed be a particular combination of circumstances which will justify in a specific case a decision not to prosecute in the public interest.
"But such decisions can only be made on a case-by-case basis, and what is imperative is that any general guidance does not obscure the bright line of the law, which must remain clear and evident to all.
"With this in mind, the Bishops' Conference will be studying the draft guidance very carefully and taking expert legal advice in preparing our own response to the consultation."