The Australian Bureau of Statistics has admitted it could have communicated with the public better about its decision to retain names and addresses from census forms for much longer than in past years.

The ABS waited until the week before Christmas to quietly announce it would retain names and addresses in separate files along with the census data in order to “provide a richer and dynamic statistical picture of Australia”. Crikey first reported the issue in January, and controversy over the proposal grew over May, June and July this year, with the ABS dismissing concerns about the privacy implications of retaining every Australian resident’s personal data for years, and boasting it had spent a lot of time discussing the issue publicly before making the decision in late 2015.

[The 2016 census is a huge threat to your privacy — boycott it]

The ABS, now somewhat humbled by the disaster of what is now called Censusfail on census night in August, is admitting that the ABS could have communicated the reason for the change and discussed it better publicly before December last year.

Speaking at the GovInnovate conference in Canberra on Wednesday, the ABS’ general manager for strategy and partnerships, Gemma van Halderen, admitted communication had not been as good as it could have been.

“The value that comes from an independent privacy impact assessment in hindsight, that is something we should have done as well,” she said, but added that the data was ultimately vital for public policy decisions and for determining the makeup of our parliament.

“We’d be a very unfortunate democracy if we were making decisions with no information out there.”

Van Halderen reiterated that legislation surrounding the census mandated the data only be used for statistical purposes, and not for surveillance. Van Halderen joked that ABS had learned from its IBM outsourcing mistake during the online census debacle and the storage of the data had not been outsourced, so it would be better protected.

But Anna Johnston, director of Salinger Privacy, said that legislation could be changed, and while the data might be protected from being used for nefarious purposes right now, all it would take is a Trump-style leader for those protections to fail.

“I don’t think that’s overstating it when you see, for example, Trump has called for the reintroduction of the demographics unit within police services in order to use demographic data to target Muslims in America,” she said.

“If you got that kind of government here — which two weeks ago I would have thought was absurd but now we know could happen anywhere in the world — the fact that your legislation says that shouldn’t happen would not stand in the way of a despotic government.”

[You’ve decided to boycott the census. Now what?]

The only real way to prevent that from happening would be to prevent the ABS from holding identifiable data, she said.

“The assurances that have been given in the past were stronger because the ABS simply didn’t retain names longer than 18 months, and the purpose for which names and addresses were used were basically just to tick off that everyone had done the census. Now there’s a whole dramatic new proposal for how it is going to be used, and there wasn’t a national conversation about that.”

Van Halderen countered the criticism around the census, suggesting that less than 1% of people the ABS had sought feedback from had said they had an issue with the retention of names and addresses. Johnston indicated that part of that was to do with concerns about the $180 per day fines for non-compliance. Johnston said she had members of the public calling her in tears saying they were Jewish and had family members persecuted in the Holocaust but didn’t want to be fined. She said she had told them to complete the census.