I found fascinating this article about the way Snowden leaked
the information about PRISM to the Guardian and Washington Post:
(I've deliberately left out some of the details in the article.)
NY Times
NOAM COHEN
June 14, 2013
Player in Leaks Case, Out From Behind Camera
<snip>
Last week, Ms. Poitras, 49, emerged as the pivotal connection between the former
government contractor Edward J. Snowden and writers for The Guardian and The Washington Post
who published his leaked documents about government surveillance.
She also got a byline on two of the papers’ resulting articles.
But she has a much longer history as a filmmaker trying to show on screen
how the world has changed since the Sept. 11 attacks.
<snip>
Mr. Snowden first contacted her in January, she said, telling her that he had read
about her regular border scrutiny and saw it as “an indicator that I was a person who was ‘selected,’*”
that is, someone who would be familiar with what it is to be watched by the government.
“He knew it was a subject that would resonate with me.”
(He had also seen a short film about domestic surveillance,
“The Program,” she made for The New York Times.)
Ms. Poitras, who won a MacArthur “genius” grant last year and
was nominated for an Oscar for “My Country,” was already
living and working outside the country.
After six years of being questioned at the border
— “upwards of 40 times, probably more, I lost count” —
and having her laptop seized, her notes copied, she relocated to Europe.
But in addition to her tense relations with her government, there was another,
more practical reason Mr. Snowden connected with her, she said.
Because of her experience reporting on national security matters, Ms. Poitras said,
she had the technical ability to hold an encrypted online conversation
with Mr. Snowden from the start, which he insisted on.
“The number of journalists who know how to use it is very small,” she said.
“You wouldn’t have been able to communicate with Snowden without encryption.”
<snip>