Every time test scores are released, a voluminous database with the results for each test taker by name goes to CTC, and smaller databases (again, by name) go to each of the other parties to whom results are reported. It wouldn't be hard for CTC and/or the universities to double-check the passing rates; in fact, Pearson or its predecessor NES has been providing teacher testing to California at least since the 1980s (CBEST, SSAT), and it would be shocking if no one had thought to check the numbers in all those years. The single most effective way to lower passing rates on test X that I've seen is to trumpet as gospel that test X is gamed, biased, and impossible to pass. Such an announcement is especially damaging to those whose confidence is already low thanks to the test scores and even teachers from whom they learned so often that they are terrible in (choose a subject area) and bad at test taking. Let me add that I have the utmost respect for teacher candidates for whom test preparation requires facing down their personal demons.