Changlng; varylng; pass-lng from one person to another by substltu-tlon. “Shlftlng the burden of proof" is transferrlng it from one party to the other, or from one slde of the case to the other, when he upon whom it rested orlglnally has made out a prima facie case or defense by evldence, of such a character that it then becomes incumbent upon the other to rebut it by contradictory or defenslve evidence
Source: Black's Law Dictionary 2nd Ed (1910)