CLINTON: “Others had done it.”

THE FACTS: Although email practices varied among her predecessors, Clinton is the only secretary of state known to have conducted all official unclassified government business on a private email address. Years earlier, when emailing was not the ubiquitous practice it is now among high officials, Colin Powell used both a government and a private account. It’s a striking departure from the norm for top officials to rely exclusively on private email for official business.

CLINTON: “I fully complied with every rule I was governed by.”

THE FACTS: At the very least, Clinton appears to have violated what the White House has called “very specific guidance” that officials should use government email to conduct business.

Clinton provided no details about whether she had initially consulted with the department or other government officials before using the private email system. She did not answer several questions about whether she sought any clearances before she began relying exclusively on private emails for government business.

Federal officials are allowed to communicate on private email and are generally allowed to conduct government business in those exchanges, but that ability is constrained, both by federal regulations and by their supervisors.

Federal law during Clinton’s tenure called for the archiving of such private email records when used for government work, but did not set out clear rules or punishments for violations until rules were tightened in November. In 2011, when Clinton was secretary, a cable from her office sent to all employees advised them to avoid conducting any official business on their private email accounts because of targeting by unspecified “online adversaries.”

CLINTON: “I did not email any classified material to anyone on my email. There is no classified material.”

THE FACTS: The assertion fits with the facts as known but skirts the issue of exchanging information in a private account that, while falling below the level of classified, is still sensitive.

The State Department and other national security agencies have specified rules for the handling of such sensitive material, which could affect national security, diplomatic and privacy concerns, and may include material such as personnel, medical and law enforcement data. In reviewing the 30,000 emails she turned over to the State Department, officials are looking for any security lapses concerning sensitive but unclassified material that may have been disclosed.

CLINTON: “It had numerous safeguards. It was on property guarded by the Secret Service. And there were no security breaches.”

THE FACTS: While Clinton’s server was physically guarded by the Secret Service, she provided no evidence it hadn’t been compromised by hackers or foreign adversaries. She also didn’t detail who administered the email system, if it received appropriate software security updates, or if it was monitored routinely for unauthorized access.

Clinton also didn’t answer whether the homebrew computer system on her property had the same level of safeguards provided at professional data facilities, such as regulated temperatures, offsite backups, generators in case of power outages and fire-suppression systems. It was unclear what, if any, encryption software Clinton’s server may have used to communicate with U.S. government email accounts.

Recent high-profile breaches, including at Sony Pictures Entertainment, have raised scrutiny on how well corporations and private individuals protect their computer networks from attack.

CLINTON: “When I got to work as secretary of state, I opted for convenience to use my personal email account, which was allowed by the State Department, because I thought it would be easier to carry just one device for my work and for my personal emails instead of two. Looking back, it would’ve been better if I’d simply used a second email account and carried a second phone, but at the time, this didn’t seem like an issue.”

THE FACTS: If multiple devices were an inconvenience in the past, they may be something of an obsession now. Clinton told an event in California’s Silicon Valley last month that she has an iPad, a mini-iPad, an iPhone and a BlackBerry. “I’m like two steps short of a hoarder,” she said. She suggested she started out in Washington with a BlackBerry but her devices grew in number.

Smartphones were capable of multiple emails when she became secretary; it’s not clear whether the particular phone she used then was permitted to do so under State Department rules.