Question Period Note: Use and Privacy Protection of Public Heath Mobility Data

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Public concerns surrounding the Public Health Agency of Canada’s (PHAC) use of mobility data emerged in response to a public posting of a Request for Proposal (RFP) on December 17, 2021, to access cell-tower/operator location data to assist in the response to the COVID-19 pandemic and for other public health applications. This RFP raised public concerns regarding individuals’ right to privacy, and concern over the Government gathering information on individuals.

Key Messages
• Reliable, timely and relevant health and public health data were crucial to inform policy and decision-making during the pandemic, and more broadly during public health emergencies and to improve long-term public health outcomes for Canadians.
• The Office of the Privacy Commissioner conducted an investigation based on complaints on the Agency’s use of mobility data and concluded the Agency did not contravene the Privacy Act.
• The Public Health Agency of Canada takes the privacy of individuals seriously and has ensured that no personal information was asked for, or received, and no individual or identifiable data was contained in mobility data received by the agency.

If pressed on user privacy
● The Public Health Agency of Canada engaged internal privacy and ethics experts to ensure the Government of Canada’s use of mobility data followed best practices. The Agency also met with the Office of the Privacy Commissioner on this initiative in April 2020 and in January 2022.
● The Public Health Agency of Canada will continue to protect user privacy by ensuring that all future Request for Proposals require that the contractors protect user privacy by only providing secure, de-identified and aggregated data. This means all personal identifiers are removed before the Agency receives the data, that it represents a population of people, and that it cannot be used to identify or track individuals.
● Consistent with previous requirements for mobility data, future proposals will also include the same requirements for individuals to easily opt out of third party vendor’s mobility data sharing programs.
● The Agency would only consider vendors who meet the Government of Canada’s strict security, legal, privacy and transparency requirements.

Mobility data is a useful tool to inform public health analysis. To date, the Public Health Agency of Canada (PHAC) has used two types of mobility data: crowdsourced mobility data and operator based mobility data (which is complementary to and used to verify crowdsourced data).
Early in the COVID-19 response, operator-based mobility data was provided to PHAC through Innovation, Science, and Economic Development’s Communication Research Centre (CRC) in partnership with TELUS Mobility.
PHAC established a sole-source contract with TELUS Mobility for this data in March 2021, which expired on October 8, 2021. PHAC also entered into a contract with BlueDot Inc. for de-identified and aggregated crowdsourced data. This contract expired on March 18, 2022.
The data received from both contracts was secure, de-identified, aggregated (i.e., not at the level of an individual), and vetted for security, legal, privacy and transparency considerations by both TELUS and PHAC.
This data helped contribute to public health insights including the ability to estimate the impacts of public health interventions and risk factors. This included using mobility data analysis to contextualize the public health situation over time, examining possible links between population movement within Canada and propagation of COVID-19, measuring the effectiveness of public health measures, and empowering Canadians with information to improve and protect their health.
From September 2020, COVIDTrends, PHAC’s COVID-19 public-facing dashboard, provided Canadians with a population movement indicator to raise awareness of mobility patterns in relation to possible easement or tightening of public health measures within their health region. Mobility data was used to support that indicator. Since the contracts with TELUS and BlueDot have now expired, the mobility indicator has been removed from the COVIDTrends website as of March 31, 2022. COVIDTrends was sunsetted in the fall of 2022.
PHAC has been producing report summaries to look at how movement trends of the Canadian population have changed over the course of the pandemic, including identifying new patterns to help direct public health messaging, planning and policy development. These summaries have been regularly shared with provinces and territories throughout the pandemic via the Special Advisory Committee.
In early fall 2021, PHAC launched an internal survey to mobility data users. Survey results indicated users find this data valuable and informative for COVID-19 situational awareness. Users also perceived the scalable potential of this data to inform other public health challenges.
PHAC launched a Request for Proposal (RFP) for its next partnership for operator-based mobility data to increase transparency and align with the Government of Canada’s “Open Data” initiatives.
An RFP was posted on the Buyandsell.gc.ca site in December 2021. In order to continue ensuring identity protection, this RFP required that the vendor supply data that has been de-identified and aggregated (i.e., not individualized) in a secure format that was vetted for security, legal, privacy and ethical considerations.
Ethics and consultations
In response to an internal request for a privacy analysis for the planned uses of mobility data, PHAC’ Privacy Management Division (PMD) concluded in August 2020 that while the data is considered sensitive, it does not contain personal information and therefore is not subject to the Privacy Act.

In January 2021, PHAC held an internal consultation with the Public Health Ethics Consultative Group (PHECG) for advice related to consent and ways to mitigate potential public concerns surrounding perception of state surveillance. PHECG provided an ethical analysis that outlined the need for PHAC to be clear about public health goals, be transparent, and to engage the public. PHAC accepted all recommendations. Due to the priority of the pandemic response, Data Management, Innovation, and Analytics was not able to conduct a public consultation.
January 6, 2022 was the most recent meeting with OPC representatives to describe the mobility data project, associated RFP, the types of analyses performed to date, and future plans to support public health. The Agency provided OPC with a very detailed presentation including data types and pipelines, epidemiological uses, privacy, and safeguards, as well as user opt-out options.
For operator data, a number of security measures—at a contractor-level, at PHAC, and through the CRC — exist to preserve the privacy and integrity of mobility data:
● Contractors must have a secure platform with clear security protocols (e.g. two-factor user identification), data that is anonymized (e.g. scrambled SIM), and ensures that precise locations are not included (e.g. location of nearest tower only)
● Analyses performed within the platform use standard codes and protocols to ensure data is de-identified.
● Prior to data extraction, anonymized user IDs are removed, data are aggregated to at least 20 devices at no smaller than census subdivision level (i.e. municipality), and measurements must be transformed into percentages. This pre-processing of mobility data prevents tracking movement patterns of individual users, including at the cell tower level.
● Exported, aggregated data are stored securely in the AWS cloud, where automated reports are created by the CRC and sent to PHAC.
● Reports generated display population-level trends within health regions (with no fewer than 20 devices) and all measurements are in proportions.
PHAC employees attended the February 2, 2022 meeting of the ETHI committee and responded to questions from the committee both directly and via remit.
On February 8, 2022, the House of Commons passed a motion calling on the government to suspend the PHAC’s cellular data tender until the ETHI Committee reports to the House that it is satisfied that the privacy of Canadians will not be affected.
As there is no option to suspend an RFP, PHAC allowed the RFP to close on February 18, 2022. PHAC allowed the RFP to expire in June 2022, as no applicant met the requirements for transparency to the public in terms of being able to provide simple opt-out. This requirement to provide options to opt out of the third party operator’s data collection was consistent with previous contracts for mobility data.

• De-identified and aggregated mobility data at the population level was used to evaluate the effectiveness of public health directives during the pandemic. By analyzing population movement data, the intent was to better understand the public’s responsiveness during lockdown measures.
• Data providers employed numerous physical controls to reduce the risk of personal information being shared or re-identified. These included deidentification methods, robust access controls and sharing processes, and aggregating data temporally and/or spatially. These controls in combination with PHAC’s own physical controls meant that PHAC did not receive any personally identifiable information (i.e. phone numbers, names, addresses) nor were there any significant risks of re-identification.
• Furthermore, PHAC expressly outlined these controls and other legal and ethical requirements in its contracts as well as in the Request for Proposal. Additionally, the data analysis was focused at the regional public health level (such as a municipality) and did not include any individually identifiable or personal information. It was used to assess macro trends in population movement and not individual movement. This was also expressly reflected in PHAC’s contracts and the Request for Proposals.
• Analyses and findings from the mobility data were regularly shared with provinces and territories as a supplemental source of information to support policy decisions and evaluation in their pandemic response.
• The Office of the Privacy Commissioner released its Report of Findings on May 30, 2023, and found that PHAC did not contravene the Privacy Act.