finding those answers fell to portland texas police detective roland chavez. mollie can't give us any information. and kristene's in the hospital, and she can't give us any information. at that point not even clear whether kristene's-- going to survive. josh mankiewicz: right. josh mankiewicz (voiceover): tips were coming in. someone said they saw a white car speeding from the park the night of the shootings. that led nowhere, so chavez and his team focused on the crime scene. there was no murder weapon. they did find two spent .45-caliber casings. and near an observation deck, just 30 feet away from where mollie and kristene were discovered, police found an empty monster energy drink can and five cigarette butts. josh mankiewicz: and the girls didn't smoke. the girls did not smoke. josh mankiewicz (voiceover): chavez sent all that for dna testing. as for the duct tape used to cover the girl's eyes, chavez thought maybe that was itself a clue. sometimes that can suggest somebody who knows the victim, didn't want to see them. mm-hmm as far as you know, either o