It's unethical (and stupid) to use IQ tests for hiring decisions because they have very little predictive power with respect to job performance.
This is incorrect.
http://www.siop.org/workplace/employment%20testing/testtypes...
http://mavweb.mnsu.edu/howard/Schmidt%20and%20Hunter%201998%...
http://geb.uni-giessen.de/geb/volltexte/2012/8532/pdf/prepri...
If a measure has such predictive power, it's not necessarily unethical to use it just because it also correlates with race.
This is true. While certainly ethical, it is still illegal in the US.