The claim that intelligence tests are culturally biased in favor of white middle-class children and are therefore invalid when applied to minority children (or to lower-class white children) is undoubtedly the commonest argument against studies of subpopulation differences. The SPSSI Council (1969) states:
We must also recognize the limitations of present-day intelligence tests. Largely developed and standardized on white middle-class children, these tests tend to be biased against black children to an unknown degree. While IQ tests do predict school achievement, we cannot demonstrate that they are accurate as measures of innate endowment. Any generalizations about the ability of black or white children are very much limited by the nature of existing IQ tests. This view has been the basis for moves to abolish all testing in
the public schools. Thus we read in a newspaper: 'The Board of Education voted unanimously last night to appoint a special committee to decide whether all psychological testing of minority children should be stopped. The resolution came after a score of black community leaders pleaded for an immediate moratorium on achievement and intelligence testing of minority children. They said the tests, designed for middle-class whites, were invalid for minority groups' (San Francisco Chronicle, 6 May 1970, p. 18). The news report quoted a psychologist as saying, 'Asking a black child the advantages of having a checking account when most black families don't have them is about as fair as asking white
children about chitterlings when most white families don't eat them.' The public is left with the clear impression that all intelligence tests are comprised of questions of factual information typical of what children in middle-or upper-class homes are most likely to learn and children from poor homes are least likely to learn. One can always point to some items or some tests which seem to illustrate this point. The next step is to brand intelligence tests as instruments of social injustice, devised and used by the Establishment to maintain the social class structure of the society. Thus an educational sociologist writes: 'In view of the close relationship between IQ scores and social class in Big City, it seems that one very destructive function of the IQ score is that it serves as a kind of cement which fixes students into the social classes of their birth. IQ is the supreme and unchallengeable justification for the social system' (Sexton, 1961, p. 51). This overlooks the fact that more than a third of the population changes social status each generation and that the correlation between SES and IQ is much higher for parents than for their children. Actually, 1Q tests, much more so than interviews, teachers' impressions, and school grades, can have a liberalizing influence on the education and upward mobility of lower-class children, since good IQ tests can 'read' through the superficial veneer of cultural factors related to social status. Many intellectually gifted children who might otherwise go undiscovered by their parents, peers and teachers are found by means of intelligence tests. As sociologist Otis Dudley Duncan (1968, p. 11) characterized this position:
. . . intelligence contributes a large share of variance in achievement (i.e., education, occupation, income) that is unrelated to the social class of birth . . . in view of the loose relationship between IQ and social class in the United States, it seems that one very constructive function of the ability measured by intelligence tests is that it serves as a kind of springboard, launching many men into achievements removing them considerable distances from the social class of their birth. 1Q, in an achievement-oriented society, is the primary leaven preventing the classes from hardening to castes.