## Facts

- Pauline Thomas worked for about six years as a manual elevator operator.
- Her elevator operator job was eliminated in August 1995 when such positions were phased out.
- In June 1996, at age 53, she applied for Social Security disability insurance benefits and Supplemental Security Income, alleging heart disease and cervical and lumbar radiculopathy.
- An Administrative Law Judge found medically determinable impairments (including hypertension, cardiac arrhythmia, and cervical/lumbar strain) but concluded she was not disabled because she could still perform her past relevant work as an elevator operator.
- Thomas argued she was “unable to do [her] previous work” under the Social Security Act because elevator operator jobs no longer existed in significant numbers in the national economy.
- The agency denied relief; the district court affirmed; the Third Circuit (en banc) reversed, reading the statute to require that past work exist in the national economy to bar benefits at step four.

## Issues

1. Whether the Social Security Administration may find a claimant not disabled at step four based solely on the claimant’s ability to perform “previous work,” without determining whether that work exists in significant numbers in the national economy under 42 U.S.C. § 423(d)(2)(A).

## Decision

- The Supreme Court reversed the Third Circuit in a unanimous decision.
- The Court held the agency may deny benefits at step four if the claimant can perform past relevant work, without inquiring whether that specific job exists in significant numbers in the national economy.
- The Court concluded the SSA’s interpretation of § 423(d)(2)(A), implemented through its five-step sequential process, is reasonable and entitled to deference under Chevron.

## Legal Principles

- The statutory disability definition sets out two requirements: (1) inability to do “previous work,” and (2) inability to engage in “any other kind of substantial gainful work which exists in the national economy.”
- The clause “which exists in the national economy” modifies “any other kind of substantial gainful work,” not “previous work.”
- The SSA may structure its sequential evaluation so that labor-market existence is addressed at step five (other work), while step four asks only whether the claimant retains the capacity to perform past relevant work.
- Under Chevron, if the statute permits more than one reading, courts must uphold an agency’s reasonable, authoritative interpretation even if it may produce harsh results in some cases.

## Conclusion

The Court held that a claimant who remains able to perform past relevant work may be found not disabled at step four, even if that specific job has largely disappeared from the national economy, because the “exists in the national economy” requirement applies to “other work” considered at step five.


Barnhart v. Thomas, 540 U.S. 20 (2003)