but detective peglo was no rookie. his investigation into charlie tan and what happened inside that home was just getting started. >> one of the investigators found what appeared to be newly taken passport photos along with a list of prom innocent local defense attorneys. >> that's interesting. >>> yes, sir. >> his theory is i had to do it but you're not taking that at face value. >> correct. >> coming up -- a discovery on jim tan's computer, suspicions about hi time of death. >> how many days prior is the last e-mail check? >> four. that was the big thing for me. yet up to 90% fall short in getting key nutrients from food alone. let's do more. add one a day men's gummies. complete with key nutrients plus b vitamins to help convert food into fuel. one a day. >>> welcome back to "dateline extra." i'm tamron hall. police arrived at the home of jim tan to find him lying behind the december income his home office, shot dead. his son, charlie, told police he did it. he said he was defending hi mother. so case closed. far fr