P was a forty-year-old former route salesman for a bakery company who suffered a serious back injury in an automobile accident on February 16, 1978. D had to undergo at least three back operations, including a fusion of the lumbar spine in October 1979. On February 4, 1980, P filed his claim for disability insurance benefits. The application was denied. P requested a hearing before an ALJ. The hearing was held on January 16, 1981, and the ALJ denied the claim. At the hearing, a fairly large amount of medical evidence was presented. It told a clear story that P was unable to engage in substantial gainful activity because of his serious back problem. D engaged her own medical adviser, Dr. Fermin Sarabia, who reviewed the medical evidence and listened to the testimony of P. The medical adviser testified that P was suffering fairly severe pain (between 7 and 8 on a scale of 10) and that the pain was organic, not psychological, in origin. At the conclusion of the medical adviser's testimony, the ALJ stated that P's case was not an easy one and that he would be required to give it very careful consideration. The ALJ then decided to follow P and his attorney as they left the courthouse where the hearing had been held. The ALJ observed P cross the street 'at a fast gait without the use of his cane,' and to enter his car 'without any obvious hesitation or difficulty.' The ALJ concluded that the claimed impairment was not of the severity expressed by P and that P's claim for disability benefits should be denied An affidavit by P's attorney directly contradicting these 'observations' was submitted to the Appeals Council. The Appeals Council affirmed the denial. P filed this action to review the administrative denial of his claim for disability benefits.