When is a tax not a tax?

Today I was reading Scalia’s dissent in Clinton v. City of New York (the case that ruled the line-item veto unconstitutional) and was struck by one of his argument, and its applicability to the ACA case:

The short of the matter is this: Had the Line Item Veto Act authorized the President to “decline to spend” any item of spending contained in the Balanced Budget Act of 1997, there is not the slightest doubt that authorization would have been constitutional. What the Line Item Veto Act does instead-authorizing the President to “cancel” an item of spending-is technically different. But the technical difference does not relate to the technicalities of the Presentment Clause, which have been fully complied with; and the doctrine of unconstitutional delegation, which is at issue here, is preeminently not a doctrine of technicalities. The title of the Line Item Veto Act, which was perhaps designed to simplify for public comprehension, or perhaps merely to comply with the terms of a campaign pledge, has succeeded in faking out the Supreme Court.

While I continue to believe that a reasonable reading of the recent (well, last 70 years) precedent on the Commerce Clause makes it clear that the mandate is a reasonable use of Congressional power in that respect, the taxation issue is another potential angle.

There really isn’t much of a meaningful difference between the mandate and a tax.  You can read it as a penalty for non-compliance.  Or you can read it as a tax, for which most people will get a tax-break (if they have insurance).  You can debate about whether this completely collapses the distinction between tax and penalty, though there is a piece here which explains a difference that makes some sense.  I haven’t really thought through whether this actually makes sense, but it seems pretty plausible.

However, the more common objection I’ve heard is simply that it wasn’t structured as a tax.  They avoided calling it a tax assiduously.  And they claim it isn’t a tax so that they can hear the case at all (since the Anti-Injunction Act) would mean the Court couldn’t even hear the case until it actually went into effect if it were a tax.  But Scalia’s reasoning here seems to eviscerate those arguments.

I assume the Court doesn’t WANT to consider it a tax, so won’t be troubled by this.  But I’m really having a hard time understanding how it’s meaningfully different.