The community of the realm in Scotland, 1249–1424
History, law and charters in a recreated kingdom
The problems with previous editions
Why do previous editions of Regiam obscure the complex manuscript history of the work?
The problems with previous editions
There is no doubt that the presence of an (im)practical manual had extraordinary authority (and indeed, we know that it worked, because a century later 'Regiam Majestatem' had become known as one of the ancient books of law of the kingdom of Scotland). But the idea of no practical use seems perhaps too far. Regiam certainly was used in later centuries - it was cited and referred to, although how, and how accurately still needs to be ascertained. But it also lessens the power of the fact that book I and much of book 2, does feel extraordinarily integrated. To add to this, the amount of 'native' material is generally underestimated. Even though we have our comparative tables of the use of Glanvill by the compiler (prepared by Thomas Thomson) we don't really know how that worked in the context of the treatise itself, and this is particularly so given that Thomson used not the earliest MSS of Regiam for his edition but a rather idiosyncratic one.
Returning to the content of Regiam, therefore, is paramount. And here we face the current lack of a good edition. Regiam Majestatem has been edited three times (although really twice): once by Sir John Skene in 1609, again by Thomas Thomson (published in 1844), and a third time by Lord Cooper in 1947 (but really this doesn't wholly count as a 'new edition', as Cooper republished Skene's text, but wrote a new and helpful introduction, as well as translated it).
There are real problems with all these editions. First, it is well known that Skene's (and therefore Cooper's) edition departs from the earliest known manuscripts of Regiam in quite substantial ways, containing chapters which are simply not there in most early MSS, and removing material which we known was there.[1] Since the labours of John Buchanan in 1937, Thomson's edition is broadly understood to be more representative of at least one early manuscript: it is mostly based on the so-called Cromertie manuscript (NLS MS Adv. 25.5.10). However, there are problems here, too. Thomson provided no critical apparatus for his edition of Regiam, leaving the authority of his text still under some suspicion. In addition, the Cromertie manuscript itself is not necessarily the best MS on which to base an archetype edition on: the MS is unfinished and the scribe seemingly made quite a few odd and certainly unfollowed elsewhere decisions about precise content, internal order, and reading.[1] In addition, the MS is glossed throughout; some of these readings seem to originate in Bute (the earliest MS to contain Regiam) but not necessarily all of them. Finally, Thomson's edition was produced without knowledge of an MS in the then British Muesum—now BL Additional MS 18111—which was rediscovered by A.A.M. Duncan, who argued (compellingly) that, although not the earliest MS, the Additional manuscript contained the earliest surviving version of the text known as Regiam Majestatem.
Everyone therefore agrees that there should be a new edition of Regiam, but the key question is what kind of edition and what should it focus on?
[1] The unique-ness of the Cromertie MS was also noted by John Buchanan ('The MSS. of Regiam Maiestatem: an experiment', Juridical Review (1937), 217-31) and T.D Fergus (ed.), Quoniam Attachiamenta (Edinburgh, 1996), and was developed further in Taylor (ed.), Laws of Medieval Scotland, pp. 393-402.