"Important questions remain about security," said Daniel Castro, vice president of the Information Technology & Innovation Foundation, shortly after Clinton's presser began. "The State Department sets the policy of what is acceptable security procedure. Connecting a State Department device to an unknown server should have raised flags internally. This gets to basic perimeter security."
"Overall, I don't see this briefing putting the matter to rest," Castro added.
Clinton's now infamous email domain, clintonemail.com, was hosted on an independently run and privately held server, an unusual move that potentially left her account exposed to hackers who would have a keen interest in reading the correspondence of the nation's top diplomat.
Part of the reason Clinton could do little Tuesday to reassure her critics is due to a series of unknowns presented by her private account that simply can't be explained away. Computer experts contend that no overtures of transparency now can erase the doubt that she may have surreptitiously destroyed emails that would be irretrievable even for the most independent and scrupulous of investigators.
"The hardest thing to do with forensics is to prove a negative," Jason Straight, chief privacy officer and senior vice president of cybersecurity at UnitedLex, a global firm that provides legal services on electronic-data discovery, told National Journal last week. "Absence of evidence is not the evidence of absence."