The Safe Conducts Act 1414 (2 Hen. 5 c.6) was an Act of the Parliament of England. It made it high treason to break a truce or promise of safe conduct by killing, robbing or "spoiling" the victim. Unusually, the "voluntary receipt" or "concealing" of people who had violated this Act was also stated to be treason.
The Act was suspended for 7 years in 1435, and permanently repealed in 1442.
References
Safe Conducts Act 1414 Wikipedia(Text) CC BY-SA