The Alexis de Tocqueville Institution (ADTI), a highly conservative think tank, will be releasing a report next week entitled Opening the Open Source Debate where they claim that government use of open source software as opposed to proprietary software is foolish. Their paper will be outlining "how open source might facilitate efforts to disrupt or sabotage electronic commerce, air traffic control or even sensitive surveillance systems."
The ADTI's logic stems from the belief that terrorists and hackers will obtain the source code to programs that the government utilizes and seek exploits that would be evident in the code, such as an unchecked buffer overflow or other bug that would allow a system to be compromised. Researchers outside the institute argue that open source software is much more secure than proprietary software because a large community shares in the code's development and bugs are fixed faster than bugs in proprietary software. Is there a correlation between having code being readily accessible and hacking? Is there a correlation between using proprietary software and not being hacked? Yes and yes, according to the ADTI.
ZDNet has coverage here.