U.S. officials say the documents show that intelligence collection programs that inadvertently intrude on Americans' privacy are found and fixed.
But they also appear to raise new questions about operations by the eavesdropping National Security Agency and its oversight by the secret U.S. Foreign Intelligence Surveillance Court (FISC).
"The court is troubled that the government's revelations regarding the NSA's acquisition of Internet transactions mark the third instance in less than three years in which the government has disclosed a substantial misrepresentation regarding the scope of a major collection program," Judge John Bates of the surveillance court wrote in one of the declassified documents.
More specifically, Bates said in an October 2011 ruling that the court had concluded that the process that resulted in improper collections of the tens of thousands of emails was "in some respects, deficient on statutory and constitutional grounds."
The newly declassified documents can be found at www.icontherecord.tumblr.com
'NOT AN EGREGIOUS OVERREACHING'
The emails in question represent only a small slice of the electronic communications scooped up around the world by the NSA. It targets about 250 million email communications for collection each year and, under a separate program, has captured and kept records of millions of phone calls by Americans.
According to the documents, only about 9 percent of the emails - or less than 25 million - are collected from "upstream" sources, which officials familiar with intelligence operations said are cable links belonging to telecommunications companies.
The rest are acquired by the NSA from Internet service providers at the point where they are sent or received. The roughly 56,000 annual emails in question were from "upstream" sources.
Intelligence officials, speaking on condition of anonymity, defended their practices.
"This is not an egregious overreaching by a greedy agency seeking to spy on Americans. This is a technological problem that resulted in an inadvertent collection of a relatively small number of U.S. person communications," a senior intelligence official told reporters.
In the newly declassified ruling of the FISA Court, the court in a footnote estimates that, based on data supplied by the NSA, between 2008 and 2011, the agency might have unintentionally collected as many as 56,000 emailed communications of Americans annually.
U.S. intelligence officials told reporters that the domestic emails were collected under a program designed to target the emails of foreign terrorism suspects.
The program does not collect emails because of flagged words such as "bomb." Instead it takes in those mentioning specific addresses, or going to or from particular addresses, one official said.
One way that emails of American citizens can get caught in the net is because the program captures the screenshot of the person's webmail account that shows a page of emails received or sent, rather than just the one targeted email, he said.
"For technological reasons NSA was not capable ... and still is not capable of breaking those down into their individual components," the official said.
'SELF-POLICING'
According to the officials and a court document which the administration released, the NSA decided to "purge" the material after discovering it was inadvertently collected.
"When you look at these documents taken as a whole, you'll get a sense for the really effective self-policing that goes on at NSA," an intelligence official said. "Any time you have a large technologically complex operation that involves thousands of people, there will mistakes, there will be errors."
The historically ultra-secretive NSA has recently taken rare steps to openly discuss classified surveillance programs after the Snowden disclosures put the Obama administration on the spot to try and explain that U.S. intelligence agencies were not deliberately spying on Americans and foreign allies.
A handful of lawmakers, most notably Senator Ron Wyden, a Democratic member of the Senate Intelligence Committee, had begun complaining months ago that the NSA was eavesdropping on Americans' communications in ways that were excessive and not transparent.
Wyden, in a statement, said the declassification of the court ruling was "long overdue" and made clear that the law as written was "insufficient to adequately protect the civil liberties and privacy rights of law-abiding Americans and should be reformed."
Intelligence officials and the declassified documents explained that one of the main reasons that the NSA inadvertently collected information on Americans without proper legal authorization was that the method used to collect emails from targeted addresses linked to foreign suspects sometimes automatically brought into the agency batches of unrelated, and purely domestic, emails. Those should not have been collected without a warrant.
Since discovering the inadvertent collection program, intelligence officials said, the NSA has tightened its procedures for spotting and getting rid of data on Americans that was collected without proper authority.
最新公布的文件顯示,美國國家安全局(NSA)通過“棱鏡”項目每年搜集全世界大約2.5億封電子郵件。
***不到3年內(nèi)越界3次
美國情報機構(gòu)21日公布的文件顯示,美國國安局在2008年至2011年間每年搜集5.6萬條美國本土與恐怖主義無關(guān)的電子郵件通信和其他電子通訊信息。
在2011年10月3日所寫的這份意見書中,美國外國情報監(jiān)視法庭首席法官約翰·貝茨說:“政府首次告知法庭它收集的信息的數(shù)量和性質(zhì)與法庭原來所認為的截然不同”。
貝茨在意見書中指出,“在不到3年的時間里,國安局的網(wǎng)絡(luò)監(jiān)控項目已經(jīng)第3次越界”,這令法庭感到不安。
據(jù)悉,這是美國政府首次公布外國情報監(jiān)視法庭的意見書,以回應一年前由美國民權(quán)組織“電子前線基金會”提出的要求。
馬克·魯莫爾德是該基金會的法務(wù)專員,他表示:“雖然經(jīng)過長達一年的訴訟和美國史上最嚴重的泄密事件,才最終讓他們公開了這份法庭意見書,這有些遺憾。但令我高興的是,美國政府終于開始正視這個問題了。”
***冰山一角
事實上,這僅僅是國安局搜集到的數(shù)量龐大的電子通訊信息中極小的一部分。意見書顯示,美國國安局每年在全世界范圍內(nèi)搜集約2.5億條電郵通信。
其中,僅有9%、也就是不到2500萬條電郵通信,是通過電信公司所有的電纜搜集情報,其余91%則是國安局通過谷歌, 雅虎和美國在線等互聯(lián)網(wǎng)服務(wù)供應商獲取。