Last week, Nouriel Roubini wrote a somewhat puzzling op-ed in the Washington Post, in support of a payroll tax cut as a stimulus measure.
It's a rather strange argument, or mix of arguments, since he's never clear whether it's a demand-side or supply-side policy. For example, he argues both that the cut should be higher for low-income workers (since they have a higher propensity to consume), and that "to maximize the incentives for private-sector hiring, there should be sharper reductions to the payroll taxes paid by employers than for those paid by employees."
But let's take the supply-side half of Roubini's argument at face value. Suppose a payroll tax cut lowered the cost of labor to employers. Is it so obvious that would increase employment?
The implicit model Roubini is using is the one every undergraduate learns, of a firm in a perfectly competitive market with increasing marginal costs. But in the real world firms face downward-sloping demand curves, especially in recessions. So the only way a reduction of labor costs can increase hiring is if it allows firms to lower costs, i.e. contributes to deflation. Does Roubini really think that more deflation is what the economy needs? (Does he even realize that's what he's arguing?)
This, anyway, was my reaction when I read the piece. But it wouldn't be worth dragging out a week-old op-ed to take shots at, if my friend Arin hadn't pointed out a recent NY Fed working paper by Gauti Eggerston making exactly this point. From the abstract: "Tax cuts can deepen a recession if the short term nominal interest rate is zero, according to a standard New Keynesian business cycle model. An example of a contractionary tax cut is a reduction in taxes on wages. This tax cut deepens a recession because it increases deflationary pressures." The paper itself involves building up a complicated model from microfoundations (that's why Eggerston gets paid the big bucks) but the underlying intuition is the same: The only way a decrease in labor costs can lead to increased hiring is by lowering prices, and under current conditions lower prices can only mean lower aggregate demand.
As Arin points out, the incoherence of the argument for payroll tax cuts may be precisely their appeal. People who think unemployment is the result of inadequate demand and people who think it's the result of lazy, overpaid workers (i.e. it's "structural") can both support them, even though the arguments are incompatible. (People who don't scruple too much over consistency can even make both arguments at once.) But if macroeconomic policy is limited to stuff that can be supported with bad arguments, we shouldn't be surprised if the results are disappointing. That lower labor costs don't help in a recession is, I guess, another lesson from the Great Depression that will have to be learned again.
As for Roubini, it's hard to improve on Jamie Galbraith's very diplomatic judgment: I cannot discern his methods.