"Mere guesswork": Clarifying the role of intelligence, mentality, and psychometric testing in the diagnosis of "mental defectives" for sterilization in Alberta from 1929 to 1972.

From 1929 until 1972, the Alberta Eugenics Board (the Board) recommended that 4,739 individuals be sterilized. The original 1928 act that legalized eugenic sterilization stipulated that the surgery itself required the consent of the individual or their caregiver; however, in 1937, the Alberta government removed the consent requirement for such cases where the Board determined individual patients to be "mental defectives." By analyzing published reports, case histories, medical journals, and primary sources from the Board, we situate the concept of "mental defective" in a historical context to clarify the Board's diagnostic process. By analyzing how the Board found individuals to be "mental defectives," we challenge a previous historiographic assumption that intelligence tests played a critical or defining role in this diagnostic process. We argue that the notion of the "mental defective" used by the Board had a long history before the advent of intelligence testing and eugenic thought. This history helps to explain how and why the Board relied extensively on the broader examination of behavior, social status, and physical appearance as core evidence in the diagnosis of "mental defect." Intelligence tests were certainly important as they shed light on an individual's academic ability. However, this alone was only one part of "mentality." Defects of mentality were understood to be broad and multifactorial, and included difficult, if not impossible, to measure attributes such as personality, emotionality, and morality. Further research should incorporate the concept of mentality in the history of psychology, testing, and eugenics. (PsycInfo Database Record (c) 2023 APA, all rights reserved).