The electoral commission’s software is shrouded in mystery and there are questions about how closely voting data reflects what is actually on the ballot

Looking out for No 1: why the Senate vote count needs greater transparency

In March, after an all-night session, the Senate passed significant changes to the way senators are elected. This legislation required a whole new system for counting Senate ballots and it needed to be done fast, with the election less than four months away.

Under the old Senate voting system, most voters didn’t mark their own preferences. They put a 1 in a box for the party of their choice and preferences flowed according to the registered party’s ticket. Only a small number of voters chose their own preferences, voting below the line. These votes made up about 3.5% of the total in 2013.

The 96.5% of ballots that were simply marked with a 1 were easy to count. Pile up the votes for each party, count how many votes are in each pile, record the total. Below-the-line votes needed to be transported to a central location in each state. Each ballot had to be individually entered in a computer including a preference for every candidate on the ballot. In 2013 there were 110 candidates in New South Wales.

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All the below-the-line preference data was then combined with the registered preferences for above-the-line votes and fed into a computer program that distributed the preferences and determined who would be elected.

All that changed with the new voting system. Voters instead mark their own preferences above the line by numbering at least six preferences, if they follow the ballot paper instructions. All these preferences are unique and need to be entered into the system individually.

The new system has also been designed to ensure that it is clear where ballot papers are at all times after 1,370 ballot papers went missing during the recount of the 2013 West Australian Senate election. There are now detailed systems to track where each ballot goes and barcoded seals on each box of ballot papers to prevent tampering.

Ballot papers were first counted on election night. They were piled up according to the party who received the first preference and this total was reported. These ballots are then sealed up and sent to the central office in each state.

In a room with a series of large printer-scanners that have been modified to take in massive Senate ballot papers, boxes are opened one by one, and if everything goes to plan the box is only open for 16 minutes before it is sealed up and put back into storage.

The rest of a count takes place on a digital copy of the ballot paper. The computer system can detect where there are marks on the ballot and will read each handwritten number. There are also humans checking each mark and making their own decision about what the ballot says – two people will do this for each ballot.

Where the computer and the humans don’t agree a ballot can be referred up to supervisors and ultimately to Australian Electoral Commission staff, who make a final decision.

All of these processes are new. It’s the first time ballot papers are being scanned at a federal level and the scale of ballot papers that need to be entered is much greater than at past elections.

Using computers to count the votes is not new, however there has been controversy over how transparent these computerised processes are.

The AEC’s Easy Count software, which is used to distribute the preferences, is private software, not auditable by experts outside of the AEC. Previous requests for the code under freedom-of-information laws have been rejected and the secrecy of the code has been criticised.

There have also been concerns raised about how difficult it is to check that voting data reflects what is actually on the ballot paper. Some have suggested that a random sample of ballots, checked manually against the data recorded in the system, would help ensure that the result is accurate.

Once the election is concluded, the AEC does release the full dataset of every preference on every ballot, which will be particularly interesting in understanding preference flows under the new voting system. This can be used to verify that the count has been conducted accurately but it would be useful to get this information sooner.

At Australian Capital Territory elections, a report is released each night of the count that calculates how preferences would flow, and who would be elected, if the count was to stop with those ballots counted so far. Such a system has not previously been needed in the Senate, because most votes flowed according to pre-registered tickets but it would be much more useful now.

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If preference data were released during the count this would also make it possible to find any possible errors in the data before the result was declared.

Such an approach would also give a lot more transparency about how much progress has been made in the Senate count. It is very difficult right now to know how many votes have been scanned and how many votes are waiting to be counted.

The Senate counting process is impressive but it is a complex system and a bit more transparency about the count would help give confidence that the result is accurate.