Barnhart

MEMORANDUM **

We AFFIRM the judgment of the district court with respect to the administrative law judge’s step three determination but REVERSE as to the ALJ’s determination at step four. We REMAND to the Commissioner for further proceedings.

*286 Substantial evidence supports the ALJ’s step three determination that Mason’s severe impairments do not meet or equal a listed impairment. The ALJ’s failure to address the combined effects of Mason’s impairments is not reversible error because Mason has failed to suggest how a combination of his impairments meets or equals a listed impairment. See Lewis v. Apfel, 236 F.3d 503, 514 (9th Cir.2001). Moreover, the ALJ did not abuse his discretion in declining to seek additional advice from a medical expert on the combined effects of Mason’s impairments.

The evidence in the record, however, is insufficient to sustain the ALJ’s step four determination that Mason was not disabled because he had the residual functional capacity (“RFC”) to perform his past relevant work. The ALJ erred in disbelieving Mason’s statements concerning his impairments and in disregarding lay testimony. The ALJ also erred in several respects in evaluating Mason’s RFC:…