In a major change to family law, the Supreme Court has ruled that a heterosexual couple should have the right to enter into a civil partnership, which is currently only available to same-sex couples.

This should mean a change in the law in the UK which will be progress, but does not go far enough to reflect the reality of modern families.

This week (on Wednesday 27 June) the Supreme Court unanimously ruled in favour of Rebecca Steinfeld and Charles Keidan from London in their bid to be allowed to have a civil partnership. Campaigners hope this will push the government to reform the law.

Civil partnerships were created in 2004 to allow gay couples to formalise their relationship to give rise to the same legal rights as married couples in terms of financial claims after separation. Then later it was considered discriminatory that gay couples couldn’t marry and since March 2014 they have had the choice of marriage or a civil partnership.

It was thought this might make civil partnerships redundant and the government recognised at the time that if the options of marriage or civil partnerships remained open only to gay couples that would be discriminatory against heterosexual couples. However, the government chose to wait and see what the public thought about the change before removing this discrimination.

It turns out there are still many couples who would rather enter into a civil partnership than get married because they don’t feel aligned with the institution of marriage.

The Supreme Court’s ruling is a welcome change and demonstrates the courts keeping pace with shifts in societal attitudes. It is now over to the government to act to remove this discrimination from UK law. However, it does still leave people who do not choose to enter into either a civil partnership or marriage vulnerable in terms of a real lack of financial rights if they split up.

There are over six million people living together as unmarried couples in the UK. And although this is the fastest growing type of family in the country, the law has not caught up. It is an urban myth that cohabitants acquire ‘common law’ rights after living together for a certain length of time, or after having children. Unfortunately there is no such thing as a ‘common law’ marriage.

The reality is that unmarried couples have very limited rights under the law if their relationship breaks down. This could lead to very unfair outcomes, even after a very long relationship of mutual support.

Giving everyone the choice of civil partnership or marriage is progress, but true equality won’t be achieved without giving more rights to cohabitants – both gay and heterosexual.

Sarah Atkinson is a partner in the family team at Stephens Scown LLP