While Clinton stressed she sent no “classified” information in her e-mails, the State Department has another category called “sensitive but unclassified.”
As of 2005, the State Department Foreign Affairs manual has stated that “sensitive but unclassified” information should not be transmitted through personal e-mail accounts.
“It is the Department’s general policy that normal day-to-day operations be conducted on an authorized AIS [Automated Information System], which has the proper level of security control to provide nonrepudiation, authentication and encryption, to ensure confidentiality, integrity, and availability of the resident information,” the manual says.
While the SBU category includes a number of technical items, such a design of embassies and payroll information, the State Department also lists “Inter or intra-agency communications, including emails, that form part of the internal deliberative processes of the U.S. Government, the disclosure of which could harm such processes.”
It’s unclear whether Clinton’s email account was conducted through a secure system that would meet State’s requirements.