In Barnhart v. Thomas (pdf), __ U.S. __ (Nov. 12, 2003), Justice Scalia, writing for a unanimous court, says
. . . [S]tep four can result in a determination of no disability without inquiry into whether the claimant’s previous work exists in the national economy; the regulations explicitly reserve inquiry into the national economy for step five. Thus, the SSA has made it perfectly clear that it does not interpret the clause “which exists in the national economy” §423(d)(2)(A) as applying to “previous work.”
Giving the Commissioner’s interpretation Chevron deference, the Court reverses the 3rd Circuit. “The proper Chevron inquiry is not whether the agency construction can give rise to undesirable results in some instances (as here both constructions can), but rather whether, in light of the alternatives, the agency construction is reasonable. In the present case, the SSA’s authoritative interpretation certainly satisfies that test.”
