In response to the news that the personal details of world leaders at the last G20 summit were accidentally disclosed by the Australian immigration department to the organisers of the Asian Cup football tournament, Ken Westin, senior security analyst at Tripwire says:
http://www.theguardian.com/world/2015/mar/30/personal-details-of-world-leaders-accidentally-revealed-by-g20-organisers
“Although this issue was caused by human error, I think one thing that many are wondering is why was email being used to send sensitive information like this in the first place. The employee accidentally included someone they shouldn’t have, however they stated "there was nothing systemic or institutional about the breach” when in fact using email to transmit sensitive data is a serious systemic and institutional security failure.”