Betty: You drugged me, Donna You put a bloody rock in my hand, but it was you or one of your demented chums that killed my boyfriend.
Donna: Fascinating theory, but here is what I think you did. Rather than try to explore to the authorities what you were doing with a bloody rock standing over Jughead’s corpse, you hid or got rid of the body. Archie and Veronica helped you, am I right? No need to answer me, I know that’s what happened, just like how I know Jughead’s body will never be found.
Betty: Yeah, why’s that?
Donna: Because if it was, all of the forensic evidence would lead to you, Betty. The crazy girlfriend with the history of mental illness. The perfect murder! No body, no crime.