Quintilian, and J.S. Watson. Institutes of Oratory. Edited by Lee Honeycutt, 2010. Kindle Electronic Edition. Book 7 Chapter 7.
It is commonly agreed that there are laws which contradict each other. This leads to many questions about both the letter and intent of those laws (Quintilian VII.7.1). A common question has to do with murder of a tyrant when the murder rescues the nation. Murder is prohibited, rescuing a nation is commanded (Quintilian VII.7.2). It is also possible for one law to contradict itself in some situations (Quintilian VII.7.3) or for similar or dissimilar laws to cause a conflict (Quintilian VII.7.4). The question in a case of conflicting laws is generally which is more binding (Quintilian VII.7.7). This may be determined based on age of the law or which violation will cause the least harm to society.