In the Anglosphere the reason quite simply is the British Empire from which most countries inherited their respective legal systems. The English Common Law is a

In the Anglosphere the reason quite simply is the British Empire from which most countries inherited their respective legal systems. The English Common Law is about a thousand years old. It saw and weathered countless kings and queens, revolutions and - most importantly - linguistic upheaval of the English language, all of which contributed to its complexity and quirkiness. An interesting example of the linguistic changes that affected legal English are legal doublets ("null and void" for instance): https://en.wikipedia.org/wiki/Legal_doublet https://en.wikipedia.org/wiki/Legal_doublet Those originally were intended precisely to avoid confusion and ambiguity. Legal doublets were an attempt to accommodate both Anglo-Saxon and French (and sometimes Latin) language roots in order to allow speakers of either to understand legal terms. To modern English speakers these terms are more of a cause for confusion rather than clarity. In addition, terms like 'null and void' nowadays add nothing to the precision of legal language but they keep being used because they're proven to work. They're a sort of legal cargo cult if you will. 'void' has exactly the same meaning as 'null and void' but we keep seeing the latter because lawyers cannot risk being linguistically progressive. They might lose a case if they don't use the terms everybody else in the legal business is used to. Hence, legal English only changes gradually and slowly.