Seems weird to me. He may have become a suspect for some unknown reason and then "confessed" to suffocating her to put her out of her misery, after he "accidentally" ran over her. But criminals often try to minimize their crimes, even while confessing.
My bet is he kidnapped her, sexually abused and then killed her. During interrogation, they may have given him an out that he took: "Look man, maybe it was an accident. Accidents happen. That doesn't make you a bad guy. We just need to know what happened so there can be some closure to this, okay?"
My bet is he kidnapped her, sexually abused and then killed her. During interrogation, they may have given him an out that he took: "Look man, maybe it was an accident. Accidents happen. That doesn't make you a bad guy. We just need to know what happened so there can be some closure to this, okay?"