Some experts, officials, and members of Congress contended that Clinton's use of a private messaging system and a private server violated federal law, specifically 18 U.S. Code § 1924, regarding the unauthorized removal and retention of classified documents or materials, as well as State Department protocols and procedures, and regulations governing recordkeeping. Clinton claimed that her use complied with federal laws and State Department regulations, and that former secretaries of state had also maintained personal email accounts (however Clinton was the only secretary of state to use a private server). News reports by NBC and CNN indicated that the emails discussed "innocuous" matters already available in the public domain. For example, the CIA drone program has been widely discussed in the public domain since the early 2000s; however, the existence of the program is technically classified, so sharing a newspaper article that mentions it would constitute a security breach, according to the CIA.