The "motivation of the suspect" has been made the main focus for prosecutors when they assess assisted dying cases, but the director of public prosecutions has denied relaxing rules on euthanasia.
Keir Starmer said there had been a "change of focus" rather than the relaxing or tightening of the rules as the Crown Prosecution Service (CPS) published permanent guidelines.
Observers said the shift away from the characteristics of the person seeking to commit suicide represented a major shift in approach, however.
Mr Starmer had been forced to publish the guidelines after the law lords called on him to clarify the factors for and against prosecution in a judgement on the Debbie Purdy case. Interim guidelines published last September are replaced by today's policy.
Among the biggest shifts is the increased prominence of compassion on the list of public interest factors tending against prosecution - although Mr Starmer said its promotion up the list was not significant.
Nevertheless a prosecution is less likely to be required, the policy states, if "the suspect was wholly motivated by compassion".
Other factors include a clear, voluntary decision of the 'victim', the extent of the suspect's actions in bringing about the suicide, and the extent to which the suspect cooperates with police officers.
Among the 16 factors tending in favour of prosecution are considerations relating to the victim's age being under 18; the victim's mental capacity to reach an informed decision; and whether the suspect was "wholly motivated by compassion".
Notes clarifying the latter underline the importance of compassion in the new policy.
"The critical element is the motive behind the suspect's act," the new guidelines state.
"If it is shown that compassion was the only driving force behind his or her actions, the fact that the suspect may have gained some benefit will not usually be treated as a factor tending in favour of prosecution."
The new policy follows a major consultation process in which nearly 5,000 responses were received by the CPS. It claimed this represented the "most extensive snapshot of public opinion since the Suicide Act 1961 was introduced.
"The policy does not change the law on assisted suicide," Mr Starmer insisted.
"It does not open the door for euthanasia. It does not override the will of parliament. What it does is to provide a clear framework for prosecutors to decide which cases should proceed to court and which should not."
Several respondents to the consultation expressed concern that those who stand to gain materially from an assisted suicide may be more likely to face prosecution as a result.
"We tried to clarify that... by making it clear a common sense approach will be taken," Mr Starmer told journalists this morning.
"The driving force - the critical motive - is the important factor. Was this an act that was driven by or motivated by gain or not? The mere fact that somebody may benefit won't necessarily put them into the category that's more or less likely for prosecution."
The country was as divided on the issue as ever as interested parties waited for Mr Starmer to announce his decision.
Most disability groups oppose assisted dying, as do religious groups and some legal bodies. But civil libertarians, single-issue activists and many members of the public sought a change in the guidance.
"We recognise that assisted suicide is a complex and emotional issue," said Richard Hawkes, chief executive of Scope, a disability organisation with a focus on people with cerebral palsy.
"However, as a charity which supports thousands of disabled people with complex support needs, we are very concerned about the potential impact of the DPP's new policy on assisted suicide.
"We know that many disabled people are genuinely frightened about any changes which risk weakening the protection offered by existing law and which could effectively create legislation by the backdoor."
Many activists and legal professionals are concerned the new guidelines will give disabled people less legal protection than able-bodied people. But pro-euthanasia groups turn that argument on its head, saying a change would grant them greater rights, given that able-bodied people are not entitled to commit suicide or secure assistance in committing suicide.
"The DPP guidelines attempt to do in part what parliament has thus far failed to, and that is to distinguish between where a person has compassionately assisted another to die, and where that was done with malicious intent or murder," said Andrew Copson, chief executive of the British Humanist Association (BHA).
But the group was wary of movement taking place on the issue without a new law being passed, branding changes to prosecution guidance 'retrospective' to the case in question.
"These guidelines will always be retrospective, after an assisted death has taken place," he went on.
"Terminally ill or incurably suffering people do not have full autonomy and choice at end of life, and those that are vulnerable are still at risk because legal safeguards, which would accompany the legalisation of assisted dying, are not in place to protect them from coercion or other malice.
"Now is the time for parliamentarians to reform the law to one that upholds people's fundamental human right to die with dignity, in a manner of their choosing."
The current law on assisted dying relies on the Suicide Act 1961, which states that a "person who aids, abets, counsels or procures the suicide of another, or an attempt by another to commit suicide, shall be liable on conviction on indictment to imprisonment for a term not exceeding 14 years".
But to date no one from the UK who has accompanied a loved one to the Dignitas clinic in Switzerland, which has helped at least 885 people end their lives, has been prosecuted.