honour code
/ˈɒnə kəʊd/(US honor code)
noun
1Any (unwritten) set of rules, customs, or principles among a particular group of people (often those otherwise considered to be unprincipled).
2 US. Also with capital initials. An official written code of moral or ethical conduct for students at a college, university, etc., forbidding practices such as plagiarism and cheating in examinations.
Origin
Mid 19th century; earliest use found in Lloyd's Weekly London Newspaper. From honour + code.