The activation of new facial recognition camera systems in Perth and Brisbane has raised concerns about how the technology is being quietly introduced by Australian governments as a way of monitoring their citizens.

Key points: Facial recognition technology will be trialled by the City of Perth for 12 months

Facial recognition technology will be trialled by the City of Perth for 12 months If successful it could be expanded to all 480 CCTV cameras in the city's network

If successful it could be expanded to all 480 CCTV cameras in the city's network But legal experts question whether it is an effective crime reduction tool

The technology was recently rolled out on the west and east coasts with little, if any, consultation with the public the government plans to watch.

Legal experts now say the public must be engaged in a debate about whether they want this powerful technology and how it could affect them in their day-to-day lives.

"We need to have a robust discussion with the community about … the types of cities we want to live in and the technology we use in them," said Monique Mann from Australian Privacy Foundation.

The City of Perth has just rolled out a 12-month-trial of the technology in 30 CCTV cameras in East Perth, with only three cameras activated to use the technology at any one time.

Facial recognition technology could be activated in this East Perth camera. ( ABC News: Rebecca Turner )

But the beleaguered authority — which is being run by Government-appointed commissioners until an inquiry into its operations is completed, following the dismissal of the city's council and mayor — is refusing to say exactly which cameras will screen citizens because of "security reasons".

Queensland sports fans and concert goers learnt this week via the media that they were being monitored with the technology at major stadiums.

As in Perth, signs at the stadiums told patrons they were being watched by CCTV but failed to mention this surveillance also included facial recognition technology which could be used by police.

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'Constantly watched and tracked'

The technology scans and stores our facial features as unique data.

It is then matched against photos — for example, pictures stored in the Federal Government's vast biometric database, which includes drivers licences, passports and those harvested from social media accounts.

City of Perth cameras will be monitored at the CityWatch surveillance centre. ( ABC News: Robert Koenig-Luck )

The technology has long been used by private companies, most notably Facebook, Amazon and Apple.

It is also considered a powerful national security tool, with the Australian Border Force using it at airport passport checkpoints.

But its growing use as a public surveillance tool concerned Dr Mann.

"There is what is termed the 'chilling effect of surveillance'," she said.

"People may not go about their regular business as they would because they're conscious of being constantly watched and tracked through physical places."

Privacy versus public safety

There have been debates around the world over the use of the technology by democratic governments, focusing on whether the public safety benefits outweigh the rights to privacy.

For example, a majority of San Francisco's board of legislators voted last month to "put the genie back in the bottle" and ban the use of the technology by its agencies, including police.

Although their city is home to some of the world's most famous tech companies which use the technology, they have asked to put a halt to its rollout.

"It's psychologically unhealthy when people know they're being watched in every aspect of the public realm, on the streets, in parks," San Francisco Supervisor Aaron Peskin said.

"That's not the kind of city I want to live in."

In the UK, a man has highlighted the weakness of regulation around the technology by taking legal action against South Wales police for breaching his human rights by taking his facial data without consent.

University of WA law school Associate Professor Julia Powles said we needed to seriously think about and debate what kind of cities we were creating if our public spaces could be monitored this way.

"What a limited vision of urban life to spy on everyone. It's ludicrous," she said.

Both Dr Mann and Associate Professor Powles said there was little evidence that the technology prevented crime.

"Honestly, in terms of the academic literature, there is really nothing that shows that it's more effective, or effective at all," Dr Mann said.

"So I'm not sure why they're rolling out and pushing it, aside from the fact that it's a technology that's available and there's an increasing uptake of it."

Data deleted after 31 days

City of Perth acting director of economic development and activation Daniel High said the technology would only be activated at the request of law enforcement authorities, such as the Australian Federal Police or WA Police.

Daniel High says the cameras will allow authorities to respond more quickly to situations. ( ABC News: Glyn Jones )

He said only the authority's community safety team and law enforcement would have access to the data, which would be deleted after 31 days.

The technology could be a powerful law enforcement tool, especially in monitoring big events at Perth Stadium.

"We feel this will enable us to respond quicker to community safety concerns and also enable us to react to situations, such as missing children et cetera … in a quicker, more efficient way," he said.

Mr High said the public had been adequately informed about use of the technology, particularly via media reports.

"There's already signs throughout the precinct highlighting that people are in a CCTV area and through the publicity et cetera that the trial has generated people will be aware that we have that capacity," he said.

Comparison images taken from Facebook

But Monash University's Professor of criminal jurisprudence, Liz Campbell, said it was best practice to inform people their images were being collected via the technology.

"There are two elements to the surveillance which people won't necessarily have consented to," she said.

"People won't know they're on a watchlist or know that an image has been taken from their Facebook page for comparison, and they may not know their picture has been taken through the live facial recognition cameras."

The technology could potentially be rolled out to all 480 CCTV cameras in the City of Perth's network. ( ABC News: Robert Koenig-Luck )

Professor Campbell said while the technology had benefits, including monitoring big crowds for potential terrorist threats, it was still new and had accuracy problems.

Research indicated that out of 10 matches only between one and three were correct, with problems in identifying women and people of colour.

"The problem is how long the timeframe is between the false match being made and the error being determined," she said.

"So it could well be the case that somebody is wrongfully stopped and maybe even being wrongfully arrested by the police if the match is an incorrect one."

Extent of facial recognition technology use unclear

Mr High said the cameras would be monitored at its surveillance centre and activated by the council's community safety officers and a WA Police officer.

"If we can contribute to things that make policing easier in our local government and keeping our residents and visitors safer, then that's something we've traditionally always done and are happy to do," he said.

WA Police will not reveal if they use facial recognition technology in other areas of policing. ( ABC News: Robert Koenig-Luck )

A WA Police spokeswoman said there were no watchlists and refused to tell the ABC whether it used facial recognition technology in other areas of its operations.

She said the City of Perth's CCTV cameras were used for investigations, prosecutions, enforcing laws and monitoring safety issues identified by either police or the authority.

If the trial is successful, the technology could be rolled out to all 480 CCTV cameras in the City of Perth's network.

Its results will be made publicly available.