The practice of certifying special usage probably did not come into general 
use until the reign of Edward I, and it was premised upon the existence of a 
common legal base to which occasional exceptions were admissible. In view 
of the pretensions to omnicompetence in the general area of customary law 
that underlay the operations of the English Curia Regis, 123 the practice was 
extensible when the base was different, but a degree of institutional similarity 
existed, e.g., the Channel Islands. It was obviously not adaptable to any situation 
where the content of the law at large was irreconcilably alien. This was 
the case with respect both to Gascony and to pre-Edwardian Wales. In the 
former dominion the customary element was set upon a Roman law base, 124 
which was in fact the common law of the region. As a practical matter this 
meant that an official conversant with customary law and relying upon forms 
and substance largely traditional was confronted with an accumulation of 
juristic writing and a body of persons adept in its use. The King of France 
recognized the need of special handling of cases from the pays de droit ecrit 
by assigning special auditors in his parlement. 126 The English crown, however, 
used the device of associating a civilian with its other functionaries, preserving 
thus the balance between custom and written law. 126 
The Welsh problem on the other hand was one involving a collision of 
profoundly different customary laws, a conflict intensified by differences of 
language and by the fact that the personal principle was still active in the 
Welsh law. During the first half of the thirteenth century, by a succession of 
special contracts between the English King and his vassal the Prince of Wales, 
the conflicts question had been regulated on a territorial principle, viz., in 
the judges" rule if applied in appeals, declared 
that the law of the case is fixed at the first instance 
(cf. the texts ibid., 114, 119). 
123 And, we hazard, the judicial activity of the 
French King's parlement. Olivier-Martin, in 
1 Histoire de la Prevote et Vicomte de Paris 
(1922), 27 et seq., has undertaken to delimit 
the expression usus et consuetudines Francii. He 
insists the parlement respected the territorial 
character of the coutumes (ibid., 33), but he 
overlooks the presumption of universal competence 
which underlay this, succincdy put by the 
Livres de justice et de plet, 11, § 6: "loi et 
costume est chose que juges doit savoir." Cf. 
further Olivier-Martin's instructive comment 
on the later coulume notoire doctrine (ibid., 83 
et seq.). 
124 The pays de droit ecrit lay south of a line 
running from Oleron, across Auvergne, north 
of Saintonge and Limousin, and so most of the 
Aquitanian lands lay within it. The local 
customs within the Roman droit commun arc 
said to number 330 (cf. Chenon, Histoire general 
du droit francais public et prive (1926), 
489). 
125 On this cf. Chenon, Le Droit romain a la 
curia regis de Philippe-Auguste a Philippe-le- 
Bel, in 1 Melanges Fitting, 197, 204 et seq. 
126 The practice in some cases rests upon inference, 
viz., the association of a cleric with 
laymen, and in other cases can be direcdy established 
as, e.g., the appointment of an identifiable 
lawyer (cf. 2 Bemont, Roles Gascons, no. 677 
[Anthony Beck, archdeacon of Durham]) or 
the employment of a legum professor (cf. 1 
Bemont, Roles Gascons, no. 262, 926 Raymond 
Sancius, 1285]; 3 Rymer, Foedera, 319 
[1312]; 4 ibid., 43 [1323]). As we shall see 
infra, the appellate jurisdiction exercised by the 
French king would in any event have forced 
the use of civilians in self-protection against 
charges for default of justice.