THE BURDEN OF PROOF, 6i But in fact, as we have seen, the record very often indeed fails to do that, and when the general issue is pleaded the denying party is often allowed in his evidence to set up affirmative defences.^ So far as the record shows us anything in such a case, the plaintiff is the actory and the burden of establishing the proposition of the case appears to be upon him. And yet, since his adversary may offer evidence of an affirmative case, and when he does, becomes the actor, and has, with his affirmation, the burden of establishing it, this burden of establishing has shifted, because a new proposition has been introduced. The real fact is, that under this mode of pleading the point of time required for setting up the affirmative case is different from that fixed where the pleading is scientific ; in- stead of requiring that it be disclosed before the pleadings are ended, it is allowed to be made known during the progress of the trial, and the sense in which we say that the burden of proof has shifted is that sense in which, under a strict rule of pleading, it would be said to shift while the pleadings are going forward, being first upon the plaintiff, " shifting " to the defendant when he pleads in confession and avoidance, and remaining fixed at the end where the last purely negative plea leaves it. In both cases the burden of estabUshing is said to "shift," in the sense that a new affirmative case has been disclosed, which carries with it the duty of making it out. It remains just as true as ever that the burden of establishing a given proposition in issue never shifts, i.e., it is always upon the actor ; but since new issues may be developed at the trial, we say that the burden of establishing shifts during the trial. Accordingly we find that Chief Justice Shaw, in the very act of starting the peculiar practice which has since existed in Massachusetts of limiting the meaning of the term "burden of proof" to the one meaning of the actor s duty of establishing his proposition, lays it down that, " Where the party having the burden of proof gives competent and prima facie evidence of a fact, and the adverse party, instead of producing proof which would go to negative the same proposition of fact, proposes to show another and a distinct proposition which avoids the effect of J- Such is a very common doctrine about the defence of contributory negligence. Ind. R.R. Co. V. Horst, 93 U. S. 291; Wakelin v. Ry. Co., 12 App. Cas. 41. In Mis- souri (Stone V, Hunt, 94 Mo. 475), as in Ireland (Dublin, etc. Ry. Co. v. Slattery, 3 App. Cas. 1 155), the defendant must plead contributory negligence specially. See Hub- bard V. Harden Exp. Co., 10 R. I. p. 254; and compare Hutch, Carriers, § 766-8. I
