Toronto, like Vancouver and New York City, is in the middle of a bonafide housing crisis. According to domestic census data, in pockets of downtown, upwards of 20 percent of owned homes are unoccupied, driving up rent. It's a speculator's market, and the situation for regular folks looking for a place to live is dire.
Mayor John Tory suggested to reporters last month that part of the solution may include a tax on people who own unoccupied homes in the city. Make no mistake—this is a very good idea. But the way the city may do it, by mining vast amounts of data related to electricity usage, is raising alarm bells.
While no clear plan has yet emerged, Mayor Tory said the city may determine who's not living in their homes by "mining" the data that smart meters send power companies to monitor electricity usage. A report on the topic of enforcing rules against property speculators is now being prepared for the mayor, the Toronto Sun reported on Sunday.
Privacy advocate and former privacy commissioner for Ontario Ann Cavoukian said that this program isn't properly implemented, it could become little more than a tool for bulk surveillance: everyone's smart meter data will presumably be scanned by the city, not just rich people's. And, she told Motherboard in an interview, it could set a precedent for smart meter data to be shared with other third parties—like police, or the courts.
Read More: Smart Meter Data Is 'Intimate' and Deserves Privacy, Activists Argue
"They're saying, 'we've got all this data, and we can go in and get whatever we want," Cavoukian said over the phone. "No, I'm sorry, the law doesn't let you do that with personally identifiable data. Restrictions on the use of the data is critical, or else you can use it for all kinds of unintended purposes that could come back and hurt the subject."
For an idea of how this might look in practice, look at how personal data from fitness trackers has been used in criminal cases as evidence. "Once you start accepting that you can use data in ways that it was never intended for, where do you stop?" Cavoukian said.
As with any bulk surveillance, there's also the risk of false positives. It's not all that uncommon for young people living on a shoestring in Toronto to keep the heat off for some of the coldest months of the year in order to save money. (Yeah, it's fucked up.) If someone gets caught in the dragnet, they'll be put in the uncomfortable position of answering to the city.
"It's very early days, but [the City] have contacted us and we will be working together with them," a spokesperson from the Information and Privacy Commissioner of Ontario told Motherboard over the phone.
Still, there's a problem to be solved here: How does the city determine who's living in their condo, and who's holding on to it so that they can flip it later for a profit? Cavoukian cedes that smart meter data may be useful, but it should be handled in an encrypted form that doesn't show the city any raw or identifiable data.
"It would only reveal to the city the cases that actually satisfy the requirements they've put in," she explained, "which may be little to no electricity usage."
Many of Cavoukian's concerns are hypothetical worst-case scenarios, since the mayor's office has reportedly only begun looking into this. But it's concerning enough that the privacy firebrand is up in arms about it, and taking a stand before it's too late.
Otherwise, we may end up with a new social ill—bulk surveillance of home smart meter data—in our attempt to stamp out an old one.
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