Sorry kids, the Roberts ruling does not make it easier for you to drink

In South Dakota v. Dole, we considered a challenge to a federal law that threatened to withhold five percent of a State’s federal highway funds if the State did not raise its drinking age to 21. … We accordingly asked whether “the financial inducement offered by Congress” was “so coercive as to pass the point at which ‘pressure turns into compulsion.’” Id., at 211 (quoting Steward Machine, supra, at 590). By “financial inducement” the Court meant the threat of losing five percent of highway funds; no new money was offered to the States to raise their drinking ages. We found that the inducement was not impermissibly coercive, because Congress was offering only “relatively mild encouragement to the States.”
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In fact, the federal funds at stake constituted less than half of one percent of South Dakota’s budget at the time. … Medicaid spending accounts for over 20 percent of the average State’s total budget, with federal funds covering 50 to 83 percent of those costs. … It is easy to see how the Dole Court could conclude that the threatened loss of less than half of one percent of South Dakota’s budget left that State with a “prerogative” to reject Congress’s desired policy, “not merely in theory but in fact.”
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The threatened loss of over 10 percent of a State’s overall budget, in contrast, is economic dragooning that leaves the States with no real option but to acquiesce in the Medicaid expansion.