[3] Per the Public Health Agency of Canada Act (2006), the CPHO holds office "during pleasure for a term not exceeding five years".

[6] The CPHO is responsible for:[7] During public health emergencies, such as outbreaks or natural disasters, the CPHO is responsible for: The chief public health officer was the head of the Public Health Agency of Canada until 2014, in which government of Prime Minister Stephen Harper reorganized the management structure of PHAC through a 2014 omnibus budget bill and instituted a parallel presidential-structure and position to govern the organization, that then could be staffed by non-medical and non-scientific personnel.

The NDP health critic said at the time that: "To bury it in an omnibus bill says to me that they don't want people to know about it and they don't want questions," while Health Minister Rona Ambrose said that "the idea for the new structure came from the agency itself," which was led at the time on an interim basis for the previous 16 months by Gregory W.

[9] She wishes to pay particular attention to the reduction of health discrepancies in the country, which includes collaborating with and reducing the socioeconomic gap of Indigenous Peoples.

Initially taking on the role in an acting capacity on December 16, 2016 following the retirement of Gregory Taylor,[2] Tam was formally appointed on June 26, 2017,[2] and led the Government of Canada's COVID-19 response in 2020.