E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Some red, some blue. In the Common Law, red bags are reserved for Q.C.s and Sergeants; but a stuff-gownsman may carry one if presented with it by a silk. Only red bags may be taken into Common Law Courts, blue must be carried no farthen than the robing-room. In Chancery Courts the etiquette is not so strict.