Medical Advisor A medical advisor is an expert witness called by the Administrative Law Judge to testify about whether the claimant meets or equals a listing, and what the claimant's Residual Functional Capacity (RFC) is. The ALJ is supposed to look at all the medical evidence on a continuum, weighing it in accordance with these principles: Give the most weight to well-supported opinions of treating doctors. Give some weight to one-time examining doctors. Give less, but still some, weight to doctors who have never examined the claimant but who have reviewed the claimant's records. These doctors might be the Social Security reviewing doctors at the first two administrative levels, or the medical advisor at the hearing. A medical advisor is supposed to be familiar with the records in the claimant's case, and may be a specialist in the claimant's type of impairment. The medical advisor will either agree or disagree with the claimant's treating doctor. The ALJ may take the medical advisor's opinion over the treating doctor's. Sometimes the ALJ will find that the Social Security doctor is more impartial or is more familiar with Social Security's rules, or that the treating doctor is merely advocating for the patient.