A bit of chicken and egg i'd say. There was hysteria at the fact that she spoke to the jury about the alleged victim's underwear. Then the story was embellished to claim that she held up the alleged victim's underwear in court, which caused more hysteria.
Her point (which I don't think was a great one) was that the jury should consider the possibility that the alleged victim was open to the idea of consensual sex on the evening in question, and that one piece of evidence to back this up was that she was wearing sexy underwear. FWIW, the accused was acquitted in the case.