What was the case Connecticut v. Teal 1982 about?
Connecticut v. Teal, 457 US 368 (1986)
In Connecticut v Teal the Court upheld Court of appeals ruling that an employer could not require an examination unrelated to the job as requisite for promotion, that this allows de facto racial discrimination. Only job-related criteria may be considered in this case. A 'Bottom line" statistics are not acceptable criteria for determining existence of discrimination -- good treatment of some members of a group does not preclude discrimination against the group as a whole or other members of the group.
In layman's terms, saying "some of my best friends are black" doesn't mean you aren't a bigot, taking those few 'acceptable' individuals to be the exception to your rule.