16/05/2014 10:14 BST | Updated 15/07/2014 06:59 BST

Common Law Marriage: A Dangerous and Pervasive Myth

Top family judge Sir James Munby made headlines recently by calling for a cohabitation law to protect women in unmarried couples.

For those of us who have seen the urgent need for change in this area, this sounds like a big step in the right direction. However, a similar recommendation was made by the Law Commission back in 2007 and we have yet to see any real change.

When an unmarried couple breaks up - no matter how long they've been together - the poorer partner has no entitlement to any financial settlement from their former other half whatsoever.

For those cohabiting with a partner, this is a fact that could have an enormous bearing on their lives, but many remain dangerously unaware of the reality.

In the vast majority of cases, those who fall foul of the myth of common-law marriage are women. Despite living with their partner for decades, often making career sacrifices to raise a family - many women find themselves left with nothing after a break-up, unable to restart a career because of their age and length of time out of employment.

We recently represented a female client who had been with her wealthy partner for 24 years and, despite giving up work to raise their children, she was entitled to literally nothing when they separated.

We see these cases pass through the courts regularly, and there have been many appeals from women who feel they have been unjustly treated. However, the law on the matter is clear, and no attempt has yet been made to improve the situation.

More unmarried couples than ever are choosing to live together. According to the ONS, the number of cohabiting pairs in the UK doubled to 2.9 million between 1996 and 2012, but the nation's lack of knowledge on this subject is extremely troubling.

Around half of the unmarried couples we deal with at JMW assume they have legal rights to a financial settlement when splitting with their partner, when in fact they have far fewer entitlements than they think. We've seen this lead to incredibly painful financial situations for individuals post-break up, and they are almost always women.

Our legal system simply has not kept pace with society in this area and this must be addressed.

It would be perfectly possible to offer a legal 'halfway house' here. I'm not suggesting we give cohabiting pairs exactly the same rights as married couples, but more needs to be done to protect vulnerable partners in the event of a split.

The rights of those who live together have been neglected for long enough; it's time to make the law more reflective of the way modern families are structured.

In the meantime, we also need to raise awareness of the importance of financial agreements between couples that intend to live together long-term, particularly those in which one partner will be dependent on the other. Cohabitation agreements are relatively straightforward to put in place, and legally binding when done properly.

These shouldn't be viewed as unromantic. Rather they should be seen - similarly to marriage - as an act of commitment as well as something that can save much emotional and financial turmoil in the future.

James Brown is a partner and family law expert at JMW Solicitors