Lucas said, “I would ask the Concerned Sister who emailed me to consider Ms. Merritt’s questions. How can you be certain of the day? That this wasn’t another day before the party? That it was Sunday night? That it was in fact Candace?”

“Yes,” Regan said. “But let’s assume that she is confident in her memory. One reason I used the bank-robbery example was because fear creates certain stressors, and memories can be clearer—or completely off. If you’re scared, you may see a threat as worse than it is or a person as physically more imposing than they are. For example, I once helped investigate a string of bank robberies because a fugitive I was pursuing was involved. The fugitive was five feet ten inches tall and one hundred sixty pounds—not a large man. Virtually every witness identified him as over six feet, and one said he had to be two hundred pounds. But it was my fugitive, who has a distinctive tattoo on his neck, and that is what ultimately identified him. Yet, of the three witnesses I personally interviewed, no one had the tattoo accurate. One said it was an eagle, one a naked woman, and one a blob of blue ink. It was in fact Pegasus from Greek mythology. They all remembered, however, that it was on the left side of his neck.

“Fear can taint memories, but it can also solidify them. Interviewers need to be careful when drawing out details from a witness. We start with easy-to-confirm facts—time of day a crime occurred, day of the week, the purpose of the witness’s visit to that location, things like that. Make the witness comfortable with mundane, easy-to-remember details, and then start asking more specific questions about the event—in fact, asking the same question in different ways can help gain more accurate information. It’s also important to keep witnesses apart. There is a very real problem of confirmation bias, when a group of witnesses will agree to something that just isn’t accurate.”

Regan hoped she wasn’t overtalking, but Lucas seemed interested in her comments. He then said, “I am hoping that A Concerned Sister will call in—or email again—with the answers to these questions. Regan, what if someone didn’t come forward during the initial investigation, would they get in trouble now if they did speak up?”

“Most likely, no,” Regan said. “First, many people didn’t even know Candace had been missing, not until her body was found. Second, the police would have questioned those most likely to have answers—the people who last saw her at the party, her roommate who reported her missing, other sorority members, her boyfriends. They would have interviewed the staff at the golf course, and then after collecting and analyzing evidence, if that led them anywhere, they would have expanded the interviews.