Investigation into the collection and use of de-identified mobility data in the course of the COVID-19 pandemic

The Office of the Privacy Commissioner of Canada (OPC) investigated 12 complaints against the Public Health Agency of Canada (PHAC) and Health Canada regarding their collection and use of de-identified mobility data during the COVID-19 pandemic. Complainants alleged PHAC secretly collected data on 33 million mobile devices. PHAC maintained it only used de-identified and aggregated data, arguing the Privacy Act did not apply as no personal information was collected. The OPC's primary issue was whether the mobility data constituted "personal information" under Section 3 of the Privacy Act, specifically if de-identification and safeguards reduced re-identification risk below the "serious possibility" threshold. The investigation examined two data streams, from TELUS and BlueDot, and assessed the de-identification techniques, aggregation levels, access controls, and contractual safeguards in place. The OPC concluded that the combination of these measures reduced the risk of identifying individuals below the "serious possibility" threshold. Consequently, the complaints were found to be not well-founded, as the data did not meet the definition of personal information under the Act. Despite this finding, the OPC made several recommendations to PHAC concerning ongoing assessment of de-identification techniques, due diligence with data providers, and enhanced transparency, which PHAC accepted.