As it turns out, the Gmail trick David Petraeus and his paramour used to hide their correspondence is one commonly employed by CIA field operatives when agency bosses turn down their pleas for more sophisticated gear to communicate with their foreign spies.
According to the Associated Press, the erstwhile CIA director and his biographer girlfriend, Paula Broadwell, shared a Gmail account that allowed them to post private notes they could each read, rather than trade emails that could easily fall into the wrong hands.
And it wasn't just an amateur dodge: the Gmail trick can be safer -- and far cheaper -- than using sophisticated "spy gear," such as encryption software, that might have drawn more scrutiny, intelligence sources say.
The Gmail sharing gambit, former agency operatives note, became a common fallback option when more sophisticated gear was deemed unnecessary or possibly even incriminating if discovered in the hands of a CIA spy.
It was used mostly to communicate with low-level spies who had access to high-level documents, such as the minutes of cabinet meetings or the blueprints for a new fighter jet.
"There are some clandestine assets who mainly provide documents -- they handle memos, plans, reports," and these people don't require frequent personal meetings, says a former deep-cover CIA officer, since "the asset did not attend the meeting where the document was discussed, approved, or knew of the decisions made."
Planting stolen documents under rocks and bridges -- so-called dead drops -- was often too risky. The agency needed better places for their spies to squirrel away the materials until they could be retrieved by their CIA handlers.
Microsoft provided the answer.
"When laptops and home computers became commonplace, even overseas, then lots of ops officers wanted [to be able to supply] their assets with ‘secure' commo -- laptops or PCs with special software that could hide a scanned copy of a document inside a normal letter or photograph," said the former deep-cover CIA officer about the sensitive espionage tradecraft.