According to the State Department Hillary Clinton handled the majority of her digital communications using her own personal e-mail address while serving as Secretary of State. The discovery was made after the Clinton team shared thousands of her governmental correspondences with the State Department in accordance with the Federal Records Act. Though it doesn't appear as if Clinton's e-mail was ever compromised, there is no way of knowing the steps that the former Secretary of State took to protect the account other than using a password.
“Personal emails are not secure,” National Security Archive director Thomas Blanton explained to The New York Times. “Senior officials should not be using them.”
Federal law dictates that all officials of Clinton's ranking are required to use their government-issued e-mail addresses that, in addition to being highly protected, are collected and maintained as a matter of record keeping.
“I can recall no instance in my time at the National Archives when a high-ranking official at an executive branch agency solely used a personal email account for the transaction of government business,” said Jason Baron, the National Archives and Records Administration's former director of litigation.
Baron went on to lambast Clinton's use of her personal email during her tenure at State:
“It is very difficult to conceive of a scenario — short of nuclear winter — where an agency would be justified in allowing its cabinet-level head officer to solely use a private email communications channel for the conduct of government business.”
Though Clinton's use of a personal e-mail account comes across as a somewhat unorthodox (and perhaps unwise) she isn't the first high-level official to maintain a person account. Her decision to forego officially sanctioned channels of communication entirely, however, is unprecedented. What penalties, if any, Clinton will face are unclear.