Why did he have to stay anywhere the day before if he flew in that day?
If he had flown in the day before, he could have stayed at a shelter, who knows?
so he knew exactly what time to arrive, what time they would leave for the party, so when he got to the house from the airport (by cab?), he could be sure the house was empty? and what time did he leave the house, did he catch a cab back to the airport on the night of Christmas Day? this isn't like Manhattan, where you walk outside and find a cab 24 hours a day.
well, the only way I will believe that is if I see airline ticket receipts.
the DNA in this case - is only a partial spread, the complete set of markers is not present (according to Henry Lee). so the DNA match, if it materializes, isn't going to be totally conclusive. the DA is going to have to definitively place him in Boulder.