Presidential Commission for the Study of Bioethical Issues 
President Barack Obama 
The White House 
1 600 Pennsylvania Avenue, NW 
Washington, DC 20500 
Dear Mr. President: 
On behalf of the Presidential Commission for the Study of Bioethical Issues, we present to you 
this report, “Ethically Impossible”: STD Research in Guatemala from 1946 to 1948. In response 
to your request of November 24, 2010, the Commission oversaw a thorough fact-finding 
investigation into the specifics of the U.S. Public Health Service-led studies in Guatemala 
involving the intentional exposure and infection of vulnerable populations. 
Following a nine-month intensive investigation, the Commission has concluded that the 
Guatemala experiments involved gross violations of ethics as judged against both the standards 
of today and the researchers’ own understanding of applicable contemporaneous practices. It is 
the Commission’s firm belief that many of the actions undertaken in Guatemala were especially 
egregious moral wrongs because many of the individuals involved held positions of public 
institutional responsibility. 
The best thing we can do as a country when faced with a dark chapter is to bring it to light. 
The Commission has worked hard to provide an unvarnished ethical analysis to both honor the 
victims and make sure events such as these never happen again. 
The Commission is also working to fulfill your other charge on human subjects research — a 
review of domestic and international contemporary human subjects protection rules and 
standards, to ensure federally funded scientific studies are conducted ethically — and will submit 
a report to you in December. 
The Commission is honored by the trust you have placed in us and grateful for the opportunity 
to serve you and the nation in this way. 
Sincerely, 
James Wagner, Ph.D. 
Vice-Chair 
Chair 
1425 New York Avenue, NW, Suite C-100, Washington, DC 20005 
Phone 202-233-3960 Fax 202-233-3990 www.bioethics.gov 
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