Not long after I joined the police force in the 1970s, I discovered that three of my friends – all women, all police officers – were being physically abused by their husbands. All three were strong and capable women. They arrested criminals. They protected the public. They handled guns.

I was shocked. I thought if violence could touch the lives of my friends, it could touch the lives of any woman.

Life has changed in so many ways since the 1970s, but violence and abuse against women and girls remains with us. Fifty-seven women have been murdered in Australia this year alone, most by men who were or are their partners.

But it's not a problem that's peculiar to Australia. In this country, one in three women report experiencing sexual, physical, emotional or financial abuse, usually at the hands of a male intimate partner or someone they know. Globally, the figures are broadly the same: one in three. That's an almost unimaginable number of 1 billion women.

The root of this violence is attitudes which devalue and exploit women and girls. Whether those attitudes are more common in developing countries than nations like our own is arguable. What is not arguable is that they still exist. And they need to change – everywhere.