The most common debating tactic of testing opponents is to avoid debate (Phelps, 2007a). Whereas scientists seek the scrutiny of their peers in order to confirm (or deny) the value of their work, advocates tend to avoid scrutiny, especially when selling falsehoods. Scientists do not circumvent the research literature, but engage it. They respond to rival hypotheses with counterevidence. They confront conflicting scientific results. Advocates, however, simply ignore them. The easiest way to win a debate is by not inviting an opponent. Testing critics rightly fear an open, fair scientific contest.

Indeed, it has become quite common for testing opponents to declare nonexistent an enormous research literature that contradicts their claims. With the help of the fourth estate (Lieberman, 2007, chapter 11), they have been fairly successful in eradicating from the collective memory thousands of studies conducted by earnest researchers over the course of a century.

In one effort of mine—accumulating studies on the effects of standardized testing—I started out thinking that there were a dozen or so. A few years ago I knew that there were hundreds. Now I know that their number exceeds a thousand. (In Phelps, 2008, Table 2 provides a brief synopsis of the research literature.)

In the end, however, it will not matter for society’s sake if we find ten thousand studies. There will remain other education researchers, prominent and with hugely abundant resources at their disposal—researchers whose work is frequently covered by U.S. education journalists—who will continue to insist that no such studies ever existed. It is U.S. education research’s dirty big secret: research that generates results that are unpopular among the vested interests can be successfully—and easily—censored and suppressed (see, for example, Phelps, 1999; 2000; 2003, Preface & chapter 7; 2005a, chapter 3).