Although the Court referred to after acquired evidence as utilized by the Supreme Court in McKennon v. Nashville Banner Publishing Co., 513 U.S. 352 (1995), it noted that this application was really different. In McKennon the issue was damages, not the prima facie case. Rather than relying on McKennon, the Court said this was really a simple case -- either she was qualified for the position or she was not. Here, there was no dispute that if the two tickets had been known she would not have been hired, and also no dispute that even if a favorable hiring decision had been made, the tickets would have been uncovered before the hiring was completed.
The objective nature of the "after acquired evidence" was the key, as the Court noted with objective facts it was less concerned with "some of the pitfalls of the use of “after acquired” evidence, such as post hoc mining of an applicant’s file to discern nondiscriminatory reasons for a failure to hire." Although holding under this narrow set of circumstances, "after acquired evidence" could defeat the prima facie case, the 11th Circuit was by no means attempting to open a wide door.
Update: Apparently having second thoughts on the unusual use of "after acquired evidence," the 11th Circuit vacated their July opinion discussed above. The end result was the same, the plaintiff lost, but this time it was her failure to show that the position for which she applied was filled by a man that was fatal to her sex discrimination claim. The Court disavowed any need to consider the "after acquired evidence" argument, that it had used as the basis for its first decision. Underwood v. Perry County Commission (11th Cir. 12/5/05) [pdf].