"The government's forensic investigation is wrestling with Snowden's apparent ability to defeat safeguards established to monitor and deter people looking at information without proper permission, said the officials, who spoke on condition of anonymity because they weren't authorized to discuss the sensitive developments publicly.
The disclosure undermines the Obama administration's assurances to Congress and the public that the NSA surveillance programs can't be abused because its spying systems are so aggressively monitored and audited for oversight purposes: If Snowden could defeat the NSA's own tripwires and internal burglar alarms, how many other employees or contractors could do the same?"
http://www.huffingtonpost.com/2013/08/24/edward-snowden-electronic-tracks_n_3809491.html