Limiting instructions and instructions to disregard inadmissible evidence are widely believed to be both ineffective and necessary. Courts presume that juries follow evidentiary instructions, but the presumption is almost universally acknowledged to be false, a kind of professional myth. This Article argues that we have it backwards. The real “myth” about evidentiary instructions is not that they work; the real myth is that they are pointless but that we need to rely on them anyway. Both of these ideas about evidentiary instructions are wrong or at best greatly exaggerated. Evidentiary instructions probably do work, although imperfectly and better under some circumstances than others. Furthermore, evidentiary instructions are not an essential part of jury trial, and the legal presumption that they work flawlessly is even less fundamental.
The conventional wisdom about evidentiary instructions—“of course they don’t work, but we have to pretend that they do”—spares us the messy but important task of assessing when evidentiary instructions are most likely to fail, how they can be made more effective, and what should follow from a recognition that they work, at best, imperfectly. It has made it easier, for example, to tolerate evidentiary instructions that are incoherent or senseless. They seem no worse, or less likely to be effective, than evidentiary instructions in general.
The conventional wisdom about evidentiary instructions is part of a broader way of thinking about lay adjudicators that holds deep appeal but that we would do well to jettison: the idea that juries are something other than groups of human beings called together to sit in judgment, that trial by jury is something other than trial by people, that the jury is not a workaday committee but a kind of intuitive, unmethodical, prediscursive oracle—the “voice of the community.” Thinking about juries as groups of people—inherently flawed, just as people are inherently flawed, but capable of reason, just as people are capable of reason—would allow us to think more sensibly and more responsibly not only about evidentiary instructions but about adjudication more generally.