Media reports tend to focus on the ease of life that such biometrics will make possible, but such "unobtrusive" biometrics remove individual permission from the biometric equation. In other words, identification processes that we would reject outright today could become tomorrow’s norm. How many people would accept having to present a driver’s licence to pick up their dry cleaning or to order fast food or respond to a classroom roll call? Yet all of these activities could eventually employ biometrics. In the case of schools, biometrics are already being trialled.

What is new, however, is the ease and breadth of today’s biometric capacity. We are already far beyond science fiction. The retinal scanning that was such an ominous feature of movies such as Minority Report feels almost old-fashioned now as seamless, more omni-present biometrics emerge. In New York, for example, residential developers are adopting solutions that are intentionally designed not to be obtrusive or even visible to those being scanned and identified. These technologies not only use a person’s face but also that person’s build, stride and voice to permit access to a building. Access will be denied to a stranger whose biometrics are not in the database.

Biometrics aren’t new. Cave painters identified their work with a hand print. Babylonian traders used their thumb prints to confirm transactions. A driver’s licence photo is a biometric. So is a signature on a piece of paper. There has long been an advantage to connecting biological characteristics with the identification of individuals. People can lie, but their bodies will still tell the truth.

This isn’t alarmism. It is conceivable that powerful tools, easy to use and supported by unprecedented computing, storage and hyper-connectivity, could become so indiscriminately and "invisibly" deployed that before long we could be living in a society in which much of our movement and behaviour is enabled, or disabled, by our identity.

However, while biometrics are indeed an important tool and will be part of future security solutions, we cannot afford "biometric creep", a situation in which we gradually cede our privacy. Now is the time to have the debate to determine what an acceptable biometric future will look like.

Who will hold all this biometric data? What rules will apply to its destruction and use? It’s easy to forget what centralised databases can be used for when they are in the wrong hands. But history is all too full of the abuses of data collected on citizens. As a society we need to continually ensure we are not creating a mechanism that a government or ruthless commercial interests can use to discriminate and oppress on grounds of race, sex, religion, obesity or anything else.

When I was a policeman, I needed warrants to obtain information held by different organisations and authorities as we built a case. Even when it came to obtaining records from different government departments, there was no carte blanche when it came to the information of private citizens. I couldn’t simply have access to everything that the government or the society knew about an individual. While that made my job more difficult, I was grateful because this impediment meant an ultimately safer society for all of us.

So what might an acceptable biometric future look like? To some extent we will need to build "impediments" into the security process and balance a desire for ease of use with deliberate restraint, as well as a mixture of innovations and time-honoured security practices. Biometrics used in conjunction with other forms of identification will likely form part of the answer. Not only will this discipline help to prevent abuse and ensure that biometrics remain a conscious part of the security equation, but it will safeguard against shortcomings in the biometric technology itself. Approaches that are already commonplace such as two-factor or three-factor security (i.e. something only the user knows; something only the user has; and something only the user is), in which each factor must be validated before authentication occurs, can help shape the model. A hand geometry reader in which a pin number needs to be entered is one example.

Most importantly, we need a framework that tempers what technology can do with what it ought to do. Given the many cybersecurity threats government, organisations and individuals are facing today, and the long-term health of our digital economy and society, such a discussion couldn’t be more urgent. We need to determine what we actually want biometrics to do.

Neil Campbell is a former Australian Federal Police officer who specialised in cybercrime, and is currently the global director of solutions at Dimension Data.