An eminent barrister, Mr J M Bennett, opposed this reform in responses to the Journal at the time. I don't support his particular objections, which I regard as muddled and reactionary. But none of the participants in this exchange succeeded in articulating a significant distinction between "must" and "shall". "Shall" ENACTS a legislative command; "must", in its ordinary usage (advocated by Eagleson and Asprey) EXPRESSES a command with authority ELSEWHERE than in the command itself.

Shakespeare's King Richard II says "6 years we banish him, and he shall go". The words of the King: the words of a statute, a performative utterance. We can imagine, however, King Richard's men, acting on that command, saying in effect "Get a move on then, you piece of scum: you must go, the King has ordered it".

This reform is emblematic of the whole plain language legislative program. Plain language sidelines the "legal" character of law and emphasises improvements in communication - in "expression" of the law. In the process, a word is chosen - "must" - which expresses obligation in preference to another word - "shall" - which enacts the obligation. The communicative and legal functions of legislation are thereby purportedly elided.

I think we need to reflect on how desirable this is. There is a difference between a brochure and an Act of parliament. The people affected by the Act need to know whether they are reading the words of the law, or someone's interpretation of the law, or a combination of both. There is a need to retain clear markers of status in both format and language, to enable law to be recognised as such.

And the use of the same "plain" style of language has potential for distortion, as I want to explore now.