Over the years, as my psychological assessment work transformed from primarily clinical to primarily forensic, we began to notice the impact on self-report validity scales (L, K, PIM, NIM, etc.); namely, they tended to elevate in evaluation  contexts where the outcome depended on a positive picture, in the under-reporting direction (so called “fake good”). Impression management has been of tremendous interest for over 50 years. As assessment psychology in general has turned more forensic this has not been overlooked by the wider field. This issue has some serious implications for the practice of psychological assessment in legal situations, especially in the way the evaluator reports the findings, and the way the findings are interpreted by decision-makers. I have been in court or have read reports of other psychologists where “moral” objections were raised by the elevated validity scales. I was asked in Federal Court, in the imperious tone often adoped by prosecutors during cross-examination, “Well, Dr. Acklin, does that elevated [MMPI-2] Lie Scale mean that the defendant is a liar?” The way that the findings are reported can have a huge prejudicial impact on the person being evaluated, typically in a high stakes situation (e.g., bail release, snetncing mitigation, or child custody evaluation). The issue raises interesting conceptual questions: Is under-reporting a personality trait? What constructs are being measured by validity scales? Is under-reporting a logical response to the situational demands of the assessment situation?  What is the role of instructions? How are you handling validity scales interpretation in your psychological evaluations? I am working on this and will have more to say later.

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