Once police have identified a suspect, they will typically place that individual into either a live or photo lineup, along with a set of "fillers." Researchers and the DOJ guidelines recommend, as a preliminary matter, that the fillers be "known innocent" non-suspects. This way, if a witness selects someone other than the suspect, the unreliability of that witness's memory is revealed. The lineup procedure can serve as a test of the witness's memory, with clear "wrong" answers. If more than one suspect is included in the lineupas in the 2006 Duke University lacrosse case, for examplethen the lineup becomes tantamount to a multiple choice test with no wrong answer.