Ashleigh Watson and Narell Majic who got married this week comfort each other after the High Court ruling. Click for more photos

Same-sex marriage laws overturned by the High Court

Ashleigh Watson and Narell Majic who got married this week comfort each other after the High Court ruling. Photo: Alex Ellinghausen

Change, regardless of the depth and extent of public support, rarely takes place without resistance or without setbacks. Enduring change is the result of persistent, incremental progress - sometimes this progress can span decades. The Greens, both nationally and here in the ACT, have been campaigning and legislating against laws that discriminate against lesbian, gay, bisexual and transgender people since the 1980s.

And, although Thursday's High Court ruling did not preserve Australia's first marriage equality legislation, the experience has provided hope and regalvanised our collective energy, as a territory and indeed as a country, to end this discrimination across the nation. In the late 1980s, when she was a Tasmanian MP fighting for gay law reform, the Greens leader, Senator Christine Milne, was labelled by opponents as 'the Mother of Teenage Sodomy'.

It was a prejudiced and difficult time for both members of the LGBTIQ community and activists campaigning for reform. Milne recalls coming up against anti-gay protesters chanting ''Kill them, kill them''. Her private member's bill was eventually passed, decriminalising homosexuality in Tasmania. More than 20 years later, the groundswell of public support for equal rights that we see now across Australia is inspiring.

The ACT has also been at the forefront of change. In 1994, we became the first Australian jurisdiction to give same-sex relationships the same legal standing as heterosexual de facto relationships.

In 2009, I proudly presented a Greens' bill that made us the first Australian jurisdiction to allow for ceremonies to validate civil unions. And just over a month ago we were the first state or territory in the country to legislate for full marriage equality. The joy that erupted in the chamber the moment that legislation passed is something I will never forget. The High Court decision on Thursday tells us that the Australian constitution and the Federal Marriage Act, in its current form, do not allow the ACT to legislate for marriage equality.

The decision does not, however, reflect morality, common sense or the growing public desire to end marriage discrimination. It should not be a deterrent, but rather a catalyst for further action. The 30 or so weddings we saw last weekend in Canberra are a testament to the hope for future change. Even while faced with the possibility of having their marriages deemed invalid by the court, the joy and excitement of those couples, and friends and families who supported them, was obvious to all.

The Abbott government has said that it challenged the ACT's marriage equality laws on constitutional grounds, rather than moral opposition. The Greens now call on Prime Minister Abbott to do what is both moral and constitutional - to act in accordance with the wishes of the majority of Australians and legislate to end marriage discrimination. In the lead-up to the Assembly debate, I spoke to many Canberrans about why marriage equality was so important.

Their responses were diverse and powerful. Some spoke of waiting decades to share their relationship with family and friends in a way the Australian community knows and celebrates. Others reflected on the love and commitment of their own heterosexual marriages. They spoke of the deep injustice they felt, that same sex relationships were not offered the same sanctity or recognition. Many simply stated that they felt their marriages were in no way threatened or diminished by others being afforded the same basic right to marry.

More than 15 countries around the world have found the courage to legislate for marriage equality. As a country that believes in a ''fair go for all'', it is time for Australia to join their ranks. When we deny a person the right to marry, we are sending a message that somehow their relationship is worth less than others; that somehow they are worth less than others. This message is wrong, it is cruel, it is outdated - and we will change it.

The path to equality is a long and unfinished journey that involves hundreds of thousands of people; activists, couples, families, mums and dads. We must have pride in what we have achieved and continue to work together to achieve equality in love for all Australians.

Greens MLA Shane Rattenbury is the Minister for Territory and Municipal Services.