How much do you think Australia's political parties know about you?

They are not legally obliged to disclose the amount of information they keep on voters and one thing the three main parties have in common is their reluctance to discuss what details they collect and how they record them.

Their databases are used to store everything from individuals' voting intentions to information about which issues are likely to swing votes so the parties can target households with specific election material.

After contacting Labor, the Coalition and the Greens, here is what we have been able to find out.

What information do political parties collect on voters?

All candidates are entitled to copies of the electoral roll containing every voter's name, age, address, occupation and whether they are a Justice of the Peace.

Labor's Queensland state secretary Evan Moorhead said the party's Campaign Central database — run by MPs and councillors' electorate offices — combined those details with contact information it purchased from Sensis and records of interactions about electorate-related enquiries, issues and door-knocking campaigns.

What parties know Political parties get your: Name

Name Age

Age Address

Address Occupation

Occupation Whether you're a Justice of the Peace What else major parties keep: Sensis contact information

Sensis contact information Your interactions with the election official and their offices

Your interactions with the election official and their offices Voting intentions (if you've told them)

The Coalition did not answer the ABC's questions about what information it kept, saying only: "During this election the Liberal National Party will be communicating with … voters about our plan for a strong new economy."

However Dennis Jensen, who has held the WA seat of Tangney as a Liberal MP since 2004 before losing preselection this year, confirmed the party's controversial Feedback database was used to collect the same kind of information Labor recorded.

A spokeswoman for Greens leader Richard Di Natale said its members "only have the electoral roll" and "details from door knocking and voters who want to hear more about Greens' policies", without elaborating.

Political parties are exempt from the Privacy Act, however, their privileged access to electoral roll data is curbed by the Electoral Act.

Parties are only allowed to use the information for certain purposes, including campaigning and maintaining the accuracy of the roll.

Last month 7.30 revealed Former NSW Labor secretary Jamie Clements had been charged with two counts of disclosing personal information for a purpose not permitted under the Parliamentary Electorates and Elections Act. He has denied the allegations.

What do they do with it?

Exactly how parties and politicians use the information they collect is unclear — even to some MPs.

Mr Moorhead said most of the information on an individual's "file" was "publicly available" and the database combined details of people who interact with the party in a professional capacity, for example as journalists and consultants, with their personal electoral roll information.

He said the information allowed parties to target their message to voters.

"Campaigning over the last 20 years has been gradually evolving and we've been moving away from big broadcast messages to very targeted messages," he said.

"If you say to me you're concerned about climate change, there's no sense in me coming to talk to you about the future of the mining industry and jobs in the resources sector."

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Dr Jensen, who is running as an independent candidate in his seat at the July 2 election, said the Feedback database worked in a similar way but electoral offices also "tagged" voters by "voting intention" and issue of concern for mail-out purposes.

He said all correspondence between a politician's office and a constituent was scanned or digitally added to the database, and at least some of the recorded information could also be accessed by Liberal Party headquarters.

"I think people expect that when they go to a member's office they'd have information recorded in some way or another … what they wouldn't expect is that they'd have voting intentions recorded and I certainly don't think they would expect that it would go further than the electorate office," he said.

A copy of the Feedback "workbook", obtained by the ABC, tells staff not to publicly discuss the program and explains how staff are trained to elicit and record voter information.

Dr Jensen said the warning not to discuss the program showed the party was sensitive about revealing how it worked.

"Clearly the parties know that even if it's not illegal, it's certainly highly unethical — if it wasn't they wouldn't have a concern about that being discussed," he said.

University of New South Wales' Cyberspace Law and Policy Community co-convenor David Vaile said political parties' exemption from the Privacy Act removed voters' right to know what information was being kept and how it was being used.

Mr Vaile said while Australian political parties' analytics programs were "probably perhaps not at the absolute peak of the massive commercial data aggregators" they were "probably some way along the line".

How securely is the information kept?

Dr Jensen said staff at the company behind Feedback, Liberal Party-owned firm Parakeelia, were difficult to contact and he was not sure what measures were in place to secure information about voters.

"It's very much a black box," he said.

For Labor's part, Mr Moorhead said: "It's all in an encrypted and verified database and it's only given to people who need to use it for their local work."

Former Labor staffer Skye Laris, who headed the party's digital campaign unit ahead of the 2013 election, said she was aware constituent information was being kept and analysed to determine campaign issues, but was not privy to details.

"There are frequent discussions about the security of information and keeping it on Australian servers and all sorts of things," she said.

"So there is a high level of awareness that this is important and necessary and [there is] a high level of awareness that information within that database would not be, could not be, shared with outside organisations."

Mr Vaile, a vice-chair of the Australian Privacy Foundation, said in the age of cyber hacking it was impossible for anyone to say data was completely protected from possible breach.

"The motivated intruder only has to find a hair's breadth crack in the defences," he said.

"Basically, the realistic thing to say is, we can't protect your data. We'll do our best, we'll protect you from weak, incompetent intruders, but anyone who's seriously motivated and sophisticated – it's quite possible that they could get through."

What is the future of data collection?

There seems to be little doubt that down the track parties' use of the information will become more sophisticated.

Ms Laris, who now runs a digital campaigning consultancy business, said it was "inevitable" Australian parties would follow the United States' lead and integrate more data to enhance their campaigns.

"I would argue that over time it would actually strengthen democracy because the risk is there is a disconnect … if you are true to your job as a member of parliament and representing your local area, it actually is really important understanding how those people are feeling and I think that ought make them better at it," she said.

"It's important people be informed and understand how that information is used."

She said in the future the public could also expect political parties to use a cache of digital data — including social media analytics and cookies — to respond to voter concerns and better target their messages online.

Mr Moorhead said: "It's getting more sophisticated because there's more you can do with data in terms of who we send mail to and that's how we primarily use it."

However, he said Australian parties would not follow the lead of their US counterparts' "big databanks" which comprise purchased financial information and even magazine subscription details.

Mr Vaile said as technology rapidly expanded to allow data collection and retention, it was crucial laws kept pace to ensure transparency.

He said the growing sophistication of analytics tools and technology could raise the spectre of subliminal political messaging.