The City of Chicago conducted an examination for firefighters in 1995. It announced it would begin selecting from among the highest scorers, called "well-qualified." The middle tier was called "qualified." Applicants who scored in this range would be kept on an eligibility list. No one brought suit attacking the examination at the time it was given.
Over time, the city exhausted the "well-qualified" list. On March 31, 1997, some African-American applicants filed a charge with the EEOC. They claimed the use of the "well qualified" score had a disparate impact on black applicants - i.e., it resulted in exclusion of a disproportionate number of black applicants. After receiving right to sue letters, they brought a class action on behalf of 6,000 "qualified" applicants.
The Court framed this issue like this:
We consider whether a plaintiff who does not file a timely charge challenging
the adoption of a practice—here, an employer’s decision to exclude employment
applicants who did not achieve a certain score on an examination—may assert
a disparate-impact claim in a timely charge challenging the employer’s later
application of that practice.
The city argued the charges were untimely and that the scoring was justified by business necessity. The city lost at trial. The district court rejected the business necessity of the test as a justification for the admittedly "severe" disparate impact.
Regarding timeliness, the plaintiffs were timely regarding the city's more recent selections of well-qualified applicants, but were untimely regarding the city's initial classification of qualified and well qualified persons.
The Supreme Court decided that the city's use, rather than adoption, of the practice was the discriminatory act. Therefore, the decision that the City's selection of well-qualified applicants within the limitations period was sufficient to establish a disparate impact claim.
The issue in Ledbetter v. Goodyear Tire & Rubber Co., 550 U. S. 618 (2007), in contrast, was whether a plaintiff could allege disparate treatment - intentional discrimination - based on time-barred past decisions. The court distinguished Ledbetter because the disparate impact claim is based on the use of neutral, but discriminatory, criteria, without the need to prove intent. So, Ledbetter is not in conflict with this decision.
The case is Lewis v. City of Chicago and the opinion is here.