recognize because when it dries, the edge of the stain will be darker than center of the stain. >> and where was ken between 12:20 p.m. to 1:40 p.m., the time of his wife's murder? >> mr. fitsue says that he had left the house around 11:30ish and had driven up to belmont, an area about 40 minutes north of where he lived to examine a vacant lot. >> no one saw ken at this lot, and ken's cell phone records showed he wasn't in that area when the school called to tell him his wife was missing. >> so ken's story, his alibi of where he was located, he was actually in the palo alto area when he received the phone call. >> prosecutors believe ken's motive was secrecy. he didn't want the divorce or anyone to know he wasn't the biological father of his oldest son, and he didn't want anyone to know they were virtually bankrupt. >> it was almost like a clock