Ancient law plays a large role in Mandate of Heaven. The term 'Mandate of Heaven' first appeared in China as a pollitical and social philosophy, the right to rule given by heaven.  In India Manu, in 2400BCE, subjugates half the species to the other half by law, Sloka V. The Romans in 200BCE gives the husband authoritative control over his wife by law, the Manus.  In Europe the right to rule is the Divine Right of Kings.  Slavery is maintained until about 1843.    

In the novel Mandate of Heaven Louise Goueffic revisits beliefs, rites and institutions of tradition and conventions established during the 4000 years of patriarchy, slavery and feudalism and places them smack in the middle of a modern context.  

Confidently assumed power and privilege in men who want to bring back the old laws has them creating a secret organization to do this and build their headquarters in a secret location.  Blatant assumption of power, ad hoc departments, old laws, torture, ancient scrolls, violence, and hard traditional attitudes play roles in their first test, an abduction of someone who refuses to obey the laws.   Modern day technology, an educated public, intelligent police force, unusual sleuth hounds, electronic planning all play in the high-speed resolution in the abduction that derails.