 A tax on sulfur dioxide emissions above 75 parts per billion per hour, by contrast, provides the firm with only a first-order reason for action. The firm regards the rate of taxation as a price on such emissions and can weigh that price against its other costs and benefits. On this account, then, a tax and a fine that create identical expected sanctions and the same distribution of type 1 and type 2 errors should induce different behaviors. The fine will never lead to higher emission rates and, under some circumstances, should induce lower emission rates. 