kathleen's body, suggesting she may have been attacked well before peterson called 9-1-1. according to prosecutors, lab tests backed that up. kathleen's head injuries had produced something called red neurons, which they say form after oxygen is withheld from the brain for at least two hours. >> that gives mr. peterson at least two hours to do things before the 9-1-1 call is placed. >> what was he doing during all that time? the state argued he was staging the scene. detectives saw what they thought were wipe marks on the stairs. to them, it was an attempt at a clean up. and there were those two wine glasses on the kitchen counter suggesting an evening of maybe too much drink, followed by a tumble down the stairs. thing was, kathleen's fingerprints weren't on either glass. in fact, the prosecution said, kathleen's blood-alcohol content was low enough that she could have passed a roadside breathalyzer test. >> she wasn't drunk.