Related Rule
Sierra Leone
Practice Relating to Rule 37. Open Towns and Non-Defended Localities
Sierra Leone’s Instructor Manual (2007) defines non-defended localities as “areas left undefended in order to protect them and their inhabitants from damage and injury”. 
Sierra Leone, The Law of Armed Conflict. Instructor Manual for the Republic of Sierra Leone Armed Forces (RSLAF), Armed Forces Education Centre, September 2007, p. 28.
Sierra Leone’s Geneva Conventions Act (2012) states:
2. Grave breaches of the [1949 Geneva] Conventions and the [1977] First [Additional] Protocol.
(1) A person of whatever nationality commits an offence if that person, whether within or outside Sierra Leone[,] commits, aids, abets or procures any other person to commit a grave breach specified in –
(e) … paragraph … 3 … of Article 85 of the First Protocol [on, inter alia, the grave breach of making non-defended localities and demilitarized zones the object of attack]. 
Sierra Leone, Geneva Conventions Act, 2012, Section 2(1)(e).