4 Innocent Agent

The innocent agent doctrine answers complicity's hardest case: the person used as an unconscious instrument — the child told to "carry this medicine" that is poison; the insane man commanded; the duress-subjected courier; the deceived clerk who "signs" the forgery.The rules:1. The innocent agent (lacking mens rea, or acting under compulsion/deception/immaturity) is not liable;2. The person who acts through the innocent agent is the principal by procuration (perpetration-by-means — Section 2's third refinement): his will is the crime's will; the agent's body was his instrument;3. Where the agent is partially culpable (the reckless courier), both may be liable — the "innocent" category shades into negligent-instrument cases;4. Comparative note: the Model Penal Code's "legal insanity or infancy of the agent" complicity clause; the Indian-Nepali abetment provisions reaching the same result through the abettor's liability even where the instigated person is incapable of offence (abetment of an incapable agent — the doctrine that closes the loophole).Illustrations to use: the classic poisons through the nurse; the child sent to deliver the "parcel" of drugs; the drunk man's keys given to the drunk friend (the giver liable as the procuring principal of the drunk driving).