What Does Jury Nullification Mean ?
In an 1893 case, our Supreme Court described jury nullification as a "naked power" possessed by the jury (People v. Lem You (1893) 97 Cal. 224, 228, 32 P. 11) but it is more than that.
The exercise of a "naked power" normally can be reversed or corrected or at least punished.
In criminal cases, however, trial courts may not enter a judgment of conviction after acquittal by a jury or grant the prosecution a new trial; nor can the prosecution seek appellate reversal of an acquittal; and, by common law rule, jurors who engage in nullification are not subject to punishment. (Bushell's Case (K.B. 1670) 124 Eng. Rep. 1006, 1012-1016; see Clark v. United States (1933) 289 U.S. 1, 17-18, 77 L. Ed. 993, 53 S. Ct. 465, In re Cochran (1924) 237 N.Y. 336, 143 N.E. 212, 212-213, Bays v. Petan Co. (D. Nev. 1982) 94 F.R.D. 587, 591.)
Therefore, rather than a mere "naked power" to ignore the law, jury nullification is more in the nature of a prerogative not to apply politically ordained criminal sanctions which conflict with the community's conscience. (United States v. Dougherty (D.C. Cir. 1972) 154 U.S. App. D.C. 76, 473 F.2d 1113, 1131.)
As previously noted, this prerogative is deeply embedded in Anglo-American jurisprudence. (Conrad, Jury Nullification (1998) pp. 13-60, a Cato Institute book.)