In the United States, we have grown accustomed to thinking of the relationship between science and government as being antagonistic.  During the most recent Bush administration, the general impression is that science has been marginalized.  American scientists have understandably looked forward to a renewed focus on science informing policy in the Obama administration.
We will restore science to its rightful place. . .
    - President Barak Obama, Inaugural Address (20 January 2009)
Accustomed to the "too little science in policy" perception, one does not think about the possibility of "too much science in policy".  Indeed, American scientists have been pre-conditioned to celebrate when policymakers ask for scientific information and act on it.    Usually, this is the territory of conspiracy theorists and wingnut intelligent design "documentaries"; but, are there situations where providing accurate scientific information to policymakers can be harmful?

In the 30 January 2009 edition of Science, a News Focus article by Richard Stone (as well as a Science Magazine Podcast segment) describes the work by a group of social scientists to predict mass social disturbances, such as large protests and riots.  As science, the ability to predict human behavior, especially in groups, is very intriguing.  The utility of these predictions remains to be tested.
If they think they can predict, let them and see if they get it right.
    -Ching Kwan Lee, sociologist at UCLA
These social scientists have enjoyed some early success (33 of 35 predictions correct) although the resolution of the predictions is not very high in space (~2000 sq km) or time (event anytime in a year).  These social scientists are giving their mass disturbance predictions to their government.  

Are there situations where providing accurate scientific information to policymakers can be harmful?  A set of predicted mass disturbances provides both the opportunity to correct the root problems and the opportunity to Police attack protestors outside Selma, AL on 7 March 1969 (from Wikipedia Commons)suppress dissent.  Scientific knowledge, which simply describes what we know about our world, is amoral.   The application of that knowledge, however, is not.  The answer comes down to your expectations for how your government will use the information.  If you learned your attitudes toward government authority from reading George Orwell, this could be quite frightening.  Melodramatic?  My government wouldn't use that information to suppress dissent, would it?  

So, who is getting this list?  The social scientists conducting this work are from the Chinese Academy of Sciences (CAS).

Thanks in part to a 2007 recommendation by the Chinese Academy of Social Sciences (CASS), the Chinese government went public by acknowledging 51,000 mass disturbances in 2005 leading to deaths, property damage, and significant response costs.  According to other research, many of the recent mass disturbances in China were caused by public frustration with widespread corruption and incompetence in local government, providing potentially simple opportunities to defuse tense situations.

The CAS researchers have positive expectations for the government of China:
But Wang and Shan don't see a dark side: They say that the central government consistently strives to rectify the poor local governance and policy failures lying at the heart of unrest.
A cynic might say that their "expectations" sounds like government boilerplate.  While the article in Science only pays lip service to the concerns of critics (one sentence), legitimate concerns are worth mentioning.  China does not have the most sparkling human rights record.  This is a country that was able to suppress reports of tens of thousands of mass disturbances until recently.  It is theoretically possible that China's government could suppress future reports and dissent.

The information, however, is now out there, kicking around cyberspace.  If the number of disturbances in China declines precipitously or there are not reports of how these situations are dealt with, curiosity will be aroused.  While it would be nice if the list of predictions was published, it would be difficult to abuse the information, because some of it is now public.  As Shan Guangai of the CASS argues, coming clean is in China's national interest:
"We want to tell the public what really happened. . .It's critical to stop rumors
from spreading."
The danger only comes when science shares information with policymakers, but not with the public.  

The CAS researchers have provided the government of China with an opportunity to correct the problems leading to mass disturbances and show that it is no longer the institution that did this:
"Tank Man" from Tiannamen Square - 5 June 1989 (photo by Jeff Widener - Associated Press)

Early returns suggest optimism.  In Weng'an province, site of a massive riot in 2008, problematic local officials were replaced with apparent success.   An application that most (not including the replaced officials) could agree with.