Social Security disability income programs have been tested by increasingly politicized concerns regarding widespread fraud among claimants. This study was an initial investigation of malingering among claimants in Los Angeles seeking disability income on psychological grounds. After a review of 100 disability income applications, a population-appropriate instrument was developed from established psychometric indices of malingering. The Composite Disability Malingering Index was completed by 167 disability claimants (possible malingerers), a sex, age and IQ cognate group of 63 psychologically disabled individuals without incentive to malinger (disabled nonmalingerers), and 45 disability examiners with instructions to malinger (instructed malingerers). The mean score of instructed malingerers and the score at the 95th percentile of the disabled nonmalingerers converged, indicating 8 as the critical score. This cutting score found 32 (19%) of disability claimants to be malingering. Self-reported substance abuse history was the only participant variable that significantly predicted higher malingering scores.