Thousands of classified US diplomatic files obtained by WikiLeaks were only made public after the password to unlock the trove was published in a book, Julian Assange's lawyer says.
Mark Summers has told Assange's extradition hearing British journalists David Leigh and Luke Harding published the password in their book WikiLeaks: Inside Julian Assange's War on Secrecy in 2011.
"Far from being a reckless, unredacted release ... what actually occurred is that one of the media partners published a book in February 2011, the password to the unredacted materials in a book, which then allowed the world to publish those unredacted materials," Summers said at London's Woolwich Crown Court on Tuesday.
"The gates got opened, not by Mr Assange or WikiLeaks."
Assange, 48, is facing a hearing to decide whether he should be extradited to the US to face 17 charges of violating the US Espionage Act and one of conspiring to commit computer intrusion.
The US government says the release of the files was reckless and that Assange knowingly put the lives of sources at risk
But Summers said WikiLeaks had initially been very cautious about releasing the files and reached out to newspapers including The Guardian, Der Speigel, Le Monde, El Pais and the New York Times.
He said they worked out a process of redaction together and the media partners had even run the redactions by representatives of the US government and the US State Department.
"The State Department initially had an active participation in the redaction process," Summers said.
German outlet Der Freitag announced they also had the password, while websites Cryptome and PirateBay published it alongside the unredacted files.
WikiLeaks repeatedly tried to warn the US State Department and the US embassy about a possibly impending leak, Summers said.
He said Assange phoned the State Department and urged them to step up their warnings to informants named in the material.
"I don't understand why you can't see this is an emergency, unless we do something, people's lives will be put at risk," Summers quoted Assange as saying in the call.
"The notion that Mr Assange knowingly put lives at risk by dumping unredacted cables is knowingly inaccurate," he said.
Earlier, Summers explained that US Army intelligence analyst Bradley Manning, who provided the documents to Assange, indicated the material was not captioned "no diss", meaning "no dissolution".
Manning indicated to Assange that the files were available to "a wide number of individuals" and there was no genuinely sensitive files in his releases to WikiLeaks.
Summers said Assange had never solicited Manning for diplomatic cables as they were not on WikiLeak's "most wanted list".
Australian Associated Press