Page:James Dawson, et ux. v. Dale W. Steager, West Virginia State Tax Commissioner.pdf/6

4 source of [his] pay or compensation,” just as §111 forbids.

The State offers this ambitious rejoinder. Even if its statute favors some state law enforcement retirees, the favored class is very small. Most state retirees are treated no better than Mr. Dawson. And this narrow preference, the State suggests, should be permitted because it affects so few people that it couldn’t meaningfully interfere with the operations of the federal government.

We are unpersuaded. Section 111 disallows any state tax that discriminates against a federal officer or employee–not just those that seem to us especially cumbersome. Nor are we inclined to accept West Virginia’s invitation to adorn §111 with a new and judicially manufactured qualification that cannot be found in its text. In fact, we have already refused an almost identical request. In Davis, we rejected Michigan’s suggestion that a discriminatory state income tax should be allowed to stand so long as it treats federal employees or retirees the same as “the vast majority of voters in the State.” 489 U. S., at 815, n. 4. We rejected, too, any suggestion that a discriminatory tax is permissible so long as it “does not interfere with the Federal Government’s ability to perform its governmental functions.” Id., at 814. In fact, as long ago as McCulloch, Chief Justice Marshall warned against enmeshing courts in the “perplexing” business, “so unfit for the judicial department,” of attempting to delineate “what degree of taxation is the legitimate use, and what degree may amount to the abuse of power.” 4 Wheat., at 430.

That’s not to say the breadth or narrowness of a state tax exemption is irrelevant. Under §111, the scope of a State’s tax exemption may affect the scope of its resulting duties. So if a State exempts from taxation all state employees, it must likewise exempt all federal employees. Conversely, if the State decides to exempt only a narrow subset of state retirees, the State can comply with §111 by exempting only the comparable class of federal retirees.