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It's a hot topic why I'm not ordering a requirement to wear #masks at this time. To be clear, in alignment with @WHO, @PHAC_GC, & @CPHO_Canada, I absolutely recommend we wear #FaceCoverings when we can't keep 2 m #PhysicalDistancing. Here are 3 reasons why I don't require it: 1/8
1. Enforcement. A public health order requires a court filing and an appearance before a judge every time one wishes to enforce it on a person/business. An order would be basically unenforceable. If we don't enforce, it's effectively just a recommendation (already done that). 2/8
2. Strength of science. While science increasingly supports #facecoverings are likely effective at slowing #COVID19 spread, research is still weak. E.g. @TheLancet systematic review finds much potential benefit, but only “low certainty” that effective. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext 3/8
. @PublicHealthON review of research finds "potentially beneficial" where physical distancing not possible, but "likely less impactful than physical distancing and hand hygiene". Ordering restriction of personal freedom needs stronger scientific basis. https://www.publichealthontario.ca/-/media/documents/ncov/covid-wwksf/what-we-know-public-masks-apr-7-2020.pdf?la=en 4/8
As well, if #facecoverings are "less impactful" & less strongly supported by scientific evidence, should we not order #physicaldistancing & #HandWashing 
before mandatory #masking or #facecovering? Debate should start with that. 5/8
before mandatory #masking or #facecovering? Debate should start with that. 5/8
3. Role of PH Orders. Why enforcement is so difficult is that PH order never intended to be used on the entire population. Use is for individuals/groups. Applying to the entire population is a novel use & legally untested. Also should an unelected official have that power? 6/8
In our democracy, when freedom on all of society needs to be restricted, it should be a decision of our elected officials. A bylaw/provincial regulation on #facecoverings would allow elected officials to decide, & enable more flexible enforcement (e.g. ticketing fines). 7/8
. @Healthmac lays out excellent points including proportionality of restricting freedom v. level of risk. None of this means we shouldn't wear #facecoverings. We should. Science supports the recommendation to do so when #PhysicalDistancing not possible. Just not a requirement. 8/8
