I think it's the outcome that matters, from an economic perspective, the consistent, harmonized carbon price across the country, which is the outcome that will minimize costs overall. That coordination could be achieved from the bottom up, between provinces coordinating with each other, or it could be achieved from the top down, with the federal government playing the coordination role. From an economic perspective, it's the outcome of harmonized policy that is most important for minimizing costs.
On January 28th, 2019. See this statement in context.