I am reading the article "The Measure and Mismeasure of Fairness: A Critical Review of Fair Machine Learning". In here there is a concept of "acting with animus", I wonder what this means in legal terms. For example (bold font added by me):
equal protection law—as established by the U.S. Constitution’s Fourteenth Amendment—prohibits government agents from acting with “discriminatory purpose” (Washington v. Davis, 1976). It bars policies undertaken with animus (i.e., it bars a form of taste-based discrimination, since acting with animus typically means sacrificing utility)
under the statutory disparate impact standard, a practice may be deemed discriminatory if it has an unjustified adverse effect on protected groups, even in the absence of explicit categorization or animus
Is it something like the will to damage minorities? How do you prove it?