To determine if the panties were something Patsy purchased, and not something brought in by the perp. A question they should have asked (maybe they did later on)was: Did JonBenet know how to read the days of the week? If not, how did she know to pick the Wednesday ones? I assume they have the rest of the package of panties? Might also be interesting to know if she wore any of the other ones, previously. Could the perp have taken this one pair after rummaging through the house and switched them in the basement? If possible, then he entered on Wednesday, the 25th.