She doesn't leave her house at night and during the day is constantly checking who is on her street.

For a life of living in fear of an abusive former partner Sarah has Centrelink to thank.

After moving hundreds of kilometres to escape him, the federal government agency shared with her ex her new location. Within months he relocated interstate to live nearby, sparking fears she'd be killed.

Eventually, after a four-year battle with Centrelink, Sarah obtained an apology and $20,000 compensation.

But the experience made her feel victimised again.

"At every turn I've been disbelieved and doubted," she says.

She discovered her ex-partner knew where she lived when he posted a screenshot of her new home from Google Maps on Facebook with the caption "CHANGE YOUR MYGOV" in May 2017.

Initially, she thought Centrelink would be horrified by its actions and remedy the mistake.

But instead, it was suggested Sarah shared the address herself.

"It was straight away not believing me at all," she says.

A complaint to the privacy regulator in September 2017 went unresolved for more than a year before the Office of the Australian Information Commissioner told Sarah it didn't believe Centrelink had interfered with her privacy.

Because she'd filled out a Centrelink form incorrectly, she was responsible for the address being shared, the letter said.

It did however acknowledge the situation was "distressing".

It was a far cry from what Australia's Privacy Commissioner Angelene Falk would conclude two and a half years later, after the OAIC changed its mind and decided to investigate.

She ruled Services Australia, the department that runs Centrelink, breached the law and ordered it to pay Sarah compensation.

Sarah's lawyer Stephen Blanks says Services Australia behaved like a private corporation rather than acting in the public interest.

It took the approach of denying any wrongdoing, deflecting responsibility for the privacy breach, instead blaming Sarah and seeking to avoid public exposure, he said.

Sarah believes Services Australia disputing her story was an extension of the abuse she suffered from her ex-partner.

During their relationship, he would constantly tell her nobody would believe her if she said he was violent and controlling.

So it was upsetting when the department denied it had breached her privacy but also her recollection of the circumstances.

"Everything they've done to handle it has just been so insulting," Sarah said.

Centrelink argued it was not responsible for a recurrence of post-traumatic stress disorder symptoms she suffered after her ex-partner learned of the new address.

He was also to blame for her fear, it said.

The agency also quibbled on costs and compensation.

More than three years after Sarah's initial complaint, in December 2020, the government offered her a settlement of $17,000.

She declined it because it wouldn't have contained public recognition of the privacy breach.

"It was never about the money," Sarah says.

"It was about them admitting it and trying to fix it so it doesn't happen again."

As part of the Privacy Commissioner's ruling last month, Services Australia was told to engage an independent auditor to examine how its systems will prevent future privacy breaches.

It's the outcome Sarah is happiest about.

"(The win) doesn't really change the fact that my partner knows where I am," she says.

"I just hope that it doesn't happen to any other women."

Sarah was fortunate her ex-partner was "a bit stupid" by alerting her on Facebook he was aware of her new address.

She fears other dangerous men won't give any warning.

"There'll be some guys that will just turn up on someone's doorstep. As has happened in the last few weeks, women will just be murdered, and nobody will ever know how they were tracked down."

The Office of the Australian Information Commissioner defended the time it took to consider the initial complaint, arguing it was a factually-complex case involving more than 600 pages of evidence.

It says Sarah's case has prompted a significant change to the department's procedures and the final determination provided "an important precedent and guidance for other cases".

Services Australia, on behalf of Centrelink, says it does not plan to appeal the Privacy Commissioner's ruling.

The agency acknowledged its processes failed to protect Sarah's privacy.

"We reiterate our deep and unreserved apology for the stress and pain caused," general manager Hank Jongen said.

Australian Associated Press