the introduction of the penis into the vagina. In the U.S., legal definitions in instances of rape or illicit sex range from state to state, but is usually thought to have taken place if the glans penis goes beyond the labia majora. In some states, if it has not taken place during carnal assault, there can't be a legal charge of rape. In such instances, the crime is some variation of felonious carnal assault, that generally has lesser punishments than those that goes along with rape.
PENETRATION: "We cannot rule out penetration at this point in the investigation until the autopsy comes back."