Caput lupinum or caput gerat lupinum is a term used in the English legal system and its derivatives. The Latin term literally means "wolf's head" or "wolfish head", and refers to a person considered to be an outlaw, as in, e.g., the phrase caput gerat lupinum ("may he wear a wolfish head" / "may his be a wolf's head"). The term was used in Medieval England to designate a person pronounced by the authorities to be a dangerous criminal, who could thus be killed without penalty. The term caput lupinum is first recorded in a law attributed to Edward the Confessor, in the text Leges Edwardi Confessoris. This law stated that a man who refused to answer a summons from the king's justice for a criminal trial would be condemned as a Caput lupinum. The thirteenth-century writer on law, Henry de Bracton, wrote in his book De Legibus et Consuetudinibus Angliae that outlaws "gerunt caput lupinum"- "bear the wolf's head." Bracton added that this meant that outlaws could thus be killed without judicial inquiry.  The fourteenth-century English legal textbook The Mirror of Justices stated that anyone who was accused of a felony, who refused three times to attend county courts, would be declared Caput lupinum or "Wolfshead". The book added ""Wolfshead!" shall be cried against him, for that a wolf is a beast hated of all folk; and from that time forward it is lawful for anyone to slay him like a wolf."  Black's Law Dictionary, 8th edition (2004: 225) reads "an outlawed felon considered a pariah – a lone wolf – open to attack by anyone." A person designated a caput lupinum was a criminal whose rights had been waived. As such, he or she could be legally harmed by any citizen.
- Southern Portland Cement v Cooper (Rodney John) (An Infant by his next friend Peter Alphonsus Cooper) Privy Council (Australia), 19 November 1973
- Menuge, Noël James (2001). Medieval English Wardship in Romance and Law. Cambridge, UK: Boydell & Brewer. p. 72. ISBN 9780859916325.
- O'Brien, Bruce R. (2015). God's Peace and King's Peace : the Laws of Edward the Confessor. Philadelphia: University of Pennsylvania Press. p. 165. ISBN 9780812234619.
- Jones, Timothy Scott (2016). Outlawry in Medieval Literature. New York: Palgrave Macmillan. p. 63. ISBN 9781349536832.