bambulshakibaei/Flickr

Sydney’s rail system uses high-tech sensors to detect tagging in progress.

The age-old cat-and-mouse game between police and graffiti artists has gotten a lot more interesting lately, with the advent of new technologies. Earlier this month, CityLab reported on the use of drones in public art and vandalism—most notably, in tagging a prominent Calvin Klein billboard in New York. But artists aren’t the only ones with tech on their side: now Sydney’s rail authority is deploying a next-generation anti-graffiti system to catch vandals in the act.

The tool, aptly named Mousetrap, uses electronic chemical sensors to detect vapors of permanent markers and spray paint in real time. As soon as Mousetrap sniffs out a tagging in progress, it alerts transit staff monitoring CCTV feeds of Sydney rail stations. Then transit police can arrest the vandals.

"Those who [create] graffiti across the network can now be sprung immediately,” Sydney transport minister Andrew Constance told the press. “With can in hand, marker in hand, doing the damage, you will get caught."

Mousetrap isn’t a perfect solution. According to the Sydney Morning Herald: “The sensors do register other smells, and it can be difficult to differentiate between the vapour of graffiti or, say, someone transporting house paint.” But since the current trial began in mid-2014, the system has already nabbed more than 30 offenders. And with a price tag of about $500,000—compared to the $34 million Sydney spent cleaning up graffiti last year—Mousetrap seems like a bargain.

One thing’s for sure: would-be taggers will have a hard time evading the long nose of the law.

About the Author

Most Popular

  1. a photo of a woman on a SkyTrain car its way to the airport in Vancouver, British Columbia.
    Transportation

    In the City That Ride-Hailing Forgot, Change Is Coming

    Fears of congestion and a powerful taxi lobby have long kept ride-hailing apps out of this transit-friendly British Columbia city. That’s about to change.  

  2. Life

    American Migration Patterns Should Terrify the GOP

    Millennial movers have hastened the growth of left-leaning metros in southern red states such as Texas, Arizona, and Georgia. It could be the biggest political story of the 2020s.

  3. Life

    Dublin Is Changing, and Locals Hate It

    The recent loss of popular murals and local pubs is fueling a deeper angst over mass tourism, redevelopment and urban transformation in the Irish capital.

  4. a photo of a bike lane in Boulder, Colorado.
    Transportation

    Why Boulder Blocked Electric Scooters

    The famously bike-friendly Colorado city has some of the best cycling infrastructure in North America. But electric scooters still aren’t welcome to use it.

  5. A photo of Providence Mayor Vincent "Buddy" Cianci Jr.,
    Life

    Un-Corrupting City Hall

    These cities all suffered notorious municipal scandals. What have officials and voters done to tackle corruption and keep it from happening again?

×