This is a little off-topic for the blog, but to understand the IRB system, it helps to understand the history of the U.S. Public Health Service, and to understand the history of the U.S. Public Health Service, it helps to read Michael Willrich's Pox: An American History, which I just finished reading and am very glad to plug.
The history of public health is a struggle between the desire for liberty and the desire for health, since many of the most effective public health measures--quarantine, health codes, compulsory vaccination, and perhaps bans on 20-ounce soft drinks--are also infringements of liberty. Willrich's account of smallpox at the turn of the twentieth century does a marvellous job at presenting both sides of this struggle. It explains laypeople's legitimate fears about the doctors and health officers who came to snatch them and their children, but also why those health officers took pride in their snatching. We may wonder who in today's IRB debate most resembles the arrogant vaccinators of a century ago: researchers seeking scientific progress, or ethics boards seeking to restrain them?