Canada's privacy czar has given a cautious thumbs-up to RCMP surveillance devices that impersonate cellphone towers and indiscriminately draw data from mobile phones.
Even so, the Office of the Privacy Commissioner of Canada (OPC) is still criticizing the Mounties for keeping silent about their use of such equipment for 12 years. This secrecy ended up not just obscuring the surveillance technique but kept the public from knowing about steps police took to protect people's privacy.
"This lack of transparency leads to serious concerns about the capability of these devices and how they are being used," the OPC said in a report. "We strongly encourage the RCMP to make efforts towards openness and accountability in terms of the technologies it employs."
Surveillance devices that spy on smartphone activity – known as IMSI catchers, cell-site simulators or by the trademark name Stingray – can allow government agents to zero in on their suspects. Police in many countries won't talk about such devices to prevent their targets from knowing about the investigative technique or because of non-disclosure agreements with suppliers.
The Canadian government's privacy watchdog released its 11-page report on Thursday morning. It is the only official government report to date on the use of such devices in Canada. Previous disclosures have come in court documents in criminal cases and an RCMP media interview earlier this year.
The privacy watchdog's report relates to use of such devices by the RCMP only, not other federal agents or municipal police forces. The OPC said its investigation had "unprecedented access" to RCMP equipment, and stressed that the IMSI-catcher models cannot spy on voice or text communications.
The RCMP machines can discern only unique digital identifiers, including international mobile subscriber identity (IMSI) numbers associated with the chips embedded in phones. Such data say nothing about who controls the phone or how they use it.
When IMSI catchers are first switched on, police draw far more data from all bystander phones in a given area than can ever be useful, the OPC report points out. "Yet over time, surveillance teams can make deductions about specific phones controlled by crime suspects. After operating [IMSI catchers] in at least three different locations … those unique identifiers can eventually be associated with the suspect of the investigation through a process of elimination."
From there, police can approach a phone company to ask for more information about the phone or who controls it. Other times, police use IMSI catchers to try to track phones already known to them – for example, those of major suspects, or a kidnapping victim.
The privacy watchdog's report on IMSI catchers follows a formal privacy complaint from OpenMedia. The B.C.-based digital-rights group pressed more than a year ago for an OPC investigation, fearing the Mounties were using the devices to conduct unlawful spying campaigns.
"Citizens are often told if they have nothing to hide they have nothing to fear," said Laura Tribe, executive director of OpenMedia. "So it seems ironic it took almost two years of external investigation to finally bring the RCMP's own secrets around over a decade of IMSI-catcher use to light."
However, the privacy watchdog body said: "We are of the view the complaint is not well-founded."
The OPC report explains that the Mounties used the surveillance devices starting in 2005. Privacy investigators then examined specifically how the RCMP used the machines in 125 criminal investigations during a five-year period, from 2011 to 2016.
But throughout, the police force used proper protocols to minimize privacy fallout – for example, by ensuring that data drawn from bystanders' phones were always withheld from investigators and later destroyed.
The police force got warrants before using IMSI catchers about 90 per cent of the time, the OPC report says.
In half of the remaining 10 per cent, police acted because they feared someone was in immediate peril. The other half involved a six-month period in 2015 when the RCMP was wrongly told by an advisory body that police didn't need judicial approval to operate IMSI catchers. Only in these six cases were police likely breaking the law, the OPC said.
The privacy watchdog still said the Mounties used the surveillance gear in "good faith."
The use of IMSI catchers by Canadian government agents was not publicly explored until 2016, when information about the practice came out in a court case centring on an RCMP-led prosecution against Quebec-based mobsters.
The police force still would not officially speak about its IMSI catchers until this spring, when a senior Mountie participated in a wide-ranging discussion with reporters from The Globe and Mail and other media outlets.