Australian law explicitly allows computers to make important decisions previously made by the ministers or staff of at least 11 federal government departments.

This has been going on since at least 2001 and despite a recent push for more openness, there remains little clarity about exactly what decisions are being entrusted to the computers.

As best we can tell, the first legislation allowing computers to automatically make important decisions with real impact on people's lives was the Social Security (Administration) Act — which also happens to be the critical piece of legislation that allowed the most high-profile and controversial automated government program so far, Centrelink's 'robodebt' endeavour.

The legislation giving computers decision-making power over social security is very short and, as these things go, easy to understand. So here it is in all its glory:

6A Secretary may arrange for use of computer programs to make decisions 1. The Secretary may arrange for the use, under the Secretary's control, of computer programs for any purposes for which the Secretary may make decisions under the social security law. 2. A decision made by the operation of a computer program under an arrangement made under subsection (1) is taken to be a decision made by the Secretary.

It was introduced in 2001 along with a slew of other provisions around debt recovery.

In the same year there were similar provisions on migration and citizenship.

So, what decisions are the computers making?

The short answer is: we don't know.

The ABC wrote to 11 departments responsible for administering legislation with computerised decision-making clauses asking for details of the decisions being made by computers.

Although some gave examples, none of the departments which responded to our questions gave a complete list of the decisions they rely on computers to make.

However, the responses did reveal a wide range of automated decision-making and vastly different levels of use across departments.

The kinds of decisions computer systems are now making range from the routine — like automatically clearing some imports — to the highly controversial, like sending debt notices to people who receive Centrelink payments.

Indeed it's important to remember that computerised decisions can be incredibly beneficial.

As Richard Chirgwin points out, it's not computers, algorithms or IT systems that are at fault when something goes wrong. It's people — politicians and department executives — who make the rules. But a lack of transparency makes it difficult to assess the quality of decisions being made by IT systems.

Australian Federal Court justice Melissa Perry noted in a 2014 speech on the topic of automated decision-making in government that "[i]n a society governed by the rule of law, administrative processes need to be transparent and accountability for their result facilitated".

You've probably been the subject of a computer's decision

It's not always obvious that government computers are making decisions about your life and until quite recently those decisions would have been made by a human.

Do you know more about important decisions being automated by government? Contact us.

For example, have you recently come back from overseas and made it all the way through immigration without speaking to a human (i.e. used the super convenient new passport scanners)?

A computer decided to let you into the country. (Or maybe flagged your entry for review by a human.)

Similarly, if you've used an app or a website to report your fortnightly income to Centrelink, the decision about how much money ends up in your account was made by a computer.

What could go wrong?

Efficiency and convenience are strong drivers for implementing these automated systems. The Department of Immigration and Border Protection told us it is "committed to exploring the applicability of and potential for emerging technologies to improve the efficiency, effectiveness and security of the Department's systems and operations".

But as Centrelink's robodebt saga makes clear, there are potential dangers lurking.

It is often suggested that automating decisions removes bias and makes systems faster, fairer and consistent.

Which algorithms affect your life? This story is part of a series ABC News is working on looking at the algorithms that affect our lives. Tell us about an algorithm you'd like to know more about.

As the Department of Human Services puts it: "Computerised decision-making can reduce red tape, ensure decisions are consistent and create greater efficiencies for recipients and the department."

But computers are only as good as the code that makes them run and the data that goes into the system. The end result can be a system that ends up making incorrect or unfair decisions that are more difficult to argue against simply because the computer can't hear your objections the same way a human decision-maker might.

Dr Darren O'Donovan, a legal academic at La Trobe University, says one of the key principles of administrative decision-making that complicates automated systems "is the obligation to give a person a chance to contribute to the eventual decision — to give them procedural fairness".

"One of the most basic rights in our society is the right to understand a decision, and engage with it," he said.

Critics of the Centrelink debt recovery process point out that even if decisions can be appealed, that doesn't prevent the process causing significant harm. They say the problems aren't just with the automated nature of the process but also with changes in the way debts are raised — which reverse the onus of proof so individuals now have to prove they were entitled to receive the benefits being claimed back rather than Centrelink having to prove they were not.

Is the Government making more automated systems?

Yes.

In recent years, there has been a new wave of legislation aiming to make similar systems legal in other portfolio areas.

Since 2010 the departments of Social Services, Health, Education and Training, Immigration and Border Protection, Agriculture and Water Resources and Veterans' Affairs have all been given some authority to let computers make decisions.

And the Government appears to be going full steam ahead in its drive for more automation.

"Information technology is an essential tool to improve the efficiency of government decision-making," the Department of Education pointed out in its response. "The department is constantly refining and developing our systems to maximise our efficiencies and deliver value for money for the Australian taxpayer."

Some people are worried about what might come next.

The most recent new powers for automated decision-making apply to the departments of Health and Veterans Affairs.

"The Department of Veterans Affairs (DVA) is undertaking veteran centric reform to significantly improve services for veterans and their families by re-engineering DVA business processes," a department spokesperson said.

And this might be a good thing. The spokesperson pointed out that "[y]ounger veterans consistently inform DVA that they would like to engage with us electronically. To enable such online services, the use of expert computer systems to make formal determinations must be legislatively sanctioned."

But others are concerned veterans may end up facing flawed processes similar to those implemented by Centrelink.