Unmarried couples who live together could be given new rights to inherit property after a death or divide assets when they separate, under plans unveiled today.
The Law Commission has launched a consultation into cohabitation to see how UK legislation can be amended to properly reflect a society where approximately two millions couples now live together out of wedlock.
The review will look at whether someone should have an automatic right to inherit property from their partner, as married couples do. Currently, cohabitants have to be granted a discretionary award by a court, dependent on their specific needs.
It will also examine how the current system for providing money for children from an unmarried relationship is working, and look at whether the unmarried equivalent of pre-nuptial agreements should be legally enforceable.
However, the rights of relatives or people who live together so one can care for the other will not be considered in the four-month consultation, nor will questions of child maintenance, custody or next of kin rights in the case of an accident.
"More people live together outside marriage than ever before. The law that applies if cohabitants separate is unacceptably complex," said project leader Stuart Bridge.
"It often gives rise to results that many people would consider unfair. We believe that there is a strong case for introducing more suitable financial remedies where cohabiting couples have children, and possibly in other circumstances."
The issue is likely to be a controversial one, with family and religious campaigners arguing that attempts to improve the legal standing of non-married couples risks undermining the institution itself.
"There is an overwhelming body of evidence from research that marriage provides the best basis for raising a stable family," said Reg Bailey, chief executive of the Mothers' Union.
"That's why it is so disappointing to see yet another government initiative that seems to undermine one of the best building blocks of strong communities."
However, Labour MP Mary Creagh, who has been campaigning on this issue for some time, welcomed the consultation as a sign that the law was catching up with society.
"We are not talking about partners claiming massive amounts of money when they separate. But these proposals will provide a safety net so that one partner is not left destitute after a long-term relationship," she said.
"People just don't realise that, legally, there is no such thing as a 'common law marriage'. There are two million unmarried couples living together in the UK. The law must catch up to give them the protection they need."
In January, the Wakefield MP tabled an early day motion condemning the "shambolic" law relating to unmarried couples and called for proper legal protection for couples who live together. It has since been signed by 121 MPs.