Hofmann acknowledged that the military "requires some level of secrecy," but added that "the public has a right to know if the Army is silencing soldiers' opinions as well."

Gordon Van Vleet, public affairs officer for the Army's Network Enterprise Technology Command/9th Signal Command, which oversees AWRAC, said he could not directly comment on the EFF lawsuit but was able to respond to written questions about the unit.

AWRAC, which is part of the Army Office of Information Assurance and Compliance, "notifies webmasters and blog writers when they find documents, pictures and other items that may compromise security," according to the Army. "AWRAC reviews for information on public web sites which may provide an adversary with sensitive information that could put soldiers or family members in danger. AWRAC assesses the risk the information poses to the military and determines if the next step is to request the information be removed."

The unit, which is based in Fort Belvoir, Va., was created in 2002. Its chief mission is looking for operations security violations, such as posted information that may put a soldier or a family member at risk, including Social Security numbers, addresses or other identifying information. The number of personnel working within the AWRAC was not released because of security concerns, according to the Army.

Using various software online search tools, the unit's personnel monitor public Web sites for sensitive information using key words such as "for official use only" or "top secret," while recording the number of times the terms are found on a site, according to the Army.