The environmental regulations US firms are exposed to are often place-based, incentivizing firms to move to less regulated counties or states. Consistent with this argument, multiplant firms partially regulated under the ozone regulations of the US Clean Air Act offset regulation-induced...

In cities around the world, Covid-19 lockdowns have improved outdoor air quality, in some cases dramatically. Even if only temporary, these improvements could have longer-lasting effects on policy by making chronic air pollution more salient and boosting political pressure for change. To that...