Transcript for Friend says teen 'wasn't fully conscious' when she was left in bedroom: Part 2
Reporter: If it's October, it means the Spanish fort toros are in familiar territory, their opponent's end zone. Closing in on another Alabama state championship. But 16-year-old Savannah is out of her league, evident to those at the party that she may have had a few too many. She's kind of just like, like, just like, going crazy walking around. Reporter: Watching from across the room, Savannah's close friend, who asked that we call her Jessica. She's drunk. Right? Mm-hmm. Reporter: What are you seeing? All of a sudden I see someone carrying her up the stairs. It was probably four people that were carrying her up the stairs, like she was a doll basically, like they just like each had a limb. And I was like, what the heck, when did this happen? I just like saw her on the couch. Reporter: But just like booze, there's something else that's ubiquitous at your typical teenage rager, cell phones. This is an image of Savannah being carried upstairs. It will later play a big part in trying to determine what occurred that night. Taylor is one of those teens who helped carry Savannah. We were all just laughing, you know, making a joke out of it, because it was funny. Everyone had been drinking, and we're carrying Savannah up, and Savannah's pretty tall, and we're all kind of short, so we were kind of struggling. Reporter: She says they did it so Savannah could lie down and sleep it off. Do you remember being carried upstairs? It's like I could hear things my eyes were shut, but I could just hear everything. I just didn't feel with it at all. Reporter: At that point, the popular seniors, newly 18, decide to leave, wanting to take the party across the bay to a club in nearby mobile. We were like, Cameron, you coming? He was like, no, I can't get in I'm just going to stay here. Reporter: Weary of trouble, because remember, Cameron Harrison is a standout senior whose football team is undefeated and entering the playoffs. Also staying behind? Savannah. And depending on who you talk to, you get conflicting reports on her state of mind. Whenever we were about to leave is whenever I saw her being carried, and she was laughing. Reporter: So you saw her being carried up the stairs? Yeah, she was like, no, I want to go back downstairs. Reporter: Once upstairs, Savannah gets sick in the bathroom. That grandma makes a brief appearance, handing her a towel. Friend "Jessica" says when she went upstairs, Savannah was barely coherent. She was just laid on the bed with like her eyes closed. And she was just like, uh-huh, I couldn't like really make out what she was saying. Reporter: Tell me, when she's saying that to you, is she unconscious at that point? She wasn't fully conscious but she wasn't fully unconscious at that point. She was probably like in-between there. She's kind of really like a zombie. Reporter: Slurring at all? Yeah, definitely slurring. But it was after that is when I noticed like, she was like, she was out. She wasn't saying anything. Reporter: Jessica says she left Savannah in that upstairs bedroom to nap but when she returned to check on her about 15 minutes later, the door was locked. I was banging on the door and I was like, what's going on? Like, why is the door locked? And I couldn't hear anything in there. And the light was off. And I remember leaving and the light was on. Reporter: She doesn't hear anything, but Cameron's teammate, Hayden, also at the door, says he hears Savannah making sounds from inside the bedroom. I heard her moaning. Like, I could hear sex noises. Reporter: Eventually the door opens, and Jessica is shocked by what she sees. So Cameron cracks the door open, and he's completely naked. And I was like, oh, my gosh. What just, what just happened? Half her body's on the bed with her arms back and then half her body's like draped off the bed. Reporter: Did she have any clothes on? She had no clothes on. She was completely naked. I started yelling at Cameron, I was like, what are you doing? Like she's obviously not okay right now. And he was like, she wanted me to. Reporter: Did it seem like she was completely out of it? Yes, completely out of it. She couldn't even move. Reporter: Couldn't move, but Jessica says Savannah did speak. And what she said would be crucial to the case. She said, just leave me here. I was mad because she said that, so that's when I left. Reporter: When Jessica goes back upstairs, another 10 or 15 minutes later, she sees Savannah disheveled. No bra and her clothes backwards and inside out. She was slumped over the toilet throwing up. And she, oh gosh, she threw up so much. Like, it was at least 20 times that night. She just kept throwing up everywhere. Reporter: And she says Cameron, nowhere in sight. Turns out he's back downstairs at the party, taking smiling snaps. No hint of potential wrongdoing. Do you remember Cameron Harrison ever being in that room with you? No. Reporter: It's approaching midnight, and on the ride home, friend Taylor says that's when Savannah whispered a secret to her. I asked her, are you okay? And she had told me, I think I had sex with Cameron. Reporter: With a sickly Savannah in the backseat, it is Jessica taking responsibility for her friend, racing home before curfew. Were you thinking, man, this girl might be in serious trouble? She might need to go to the hospital right now. Oh, yeah. I wanted to take her there, but she would just start screaming, she's like, no. She was still drunk at that point but she would try her best to be like, mm-mm, no, you can't do that. Reporter: With her parents asleep, Jessica sneaks the two of them in through the side door. Savannah still vomiting. She was still shaking, she was ke white, white. I put so many blankets on her and she was still, she kept on saying like I'm so cold, like, it sounded like she was just like in like a freezer. Reporter: For two hours "Jessica" stood watch over her intoxicated friend.
This transcript has been automatically generated and may not be 100% accurate.