Barack Obama's team used NSA technology to examine data gathered on tens of thousands of Americans abroad during the election, it has emerged.
Officials searched both metadata and the actual contents of communications for the names of more than 30,000 US citizens, according to data released by the he Office of the Director of National Intelligence this week.
And more than 3,000 of the resulting intelligence reports were then circulated among government departments without the names of the searched parties being redacted, sources with direct knowledge told Circa.
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I, spy? Barack Obama's team searched NSA data for info on US citizens including Donald Trump's election team, insiders claimed Wednesday. Legally, the NSA can't spy on US citizens
The data is officially only gathered on non-US-citizens outside America that use US infrastructure such as email servers.
But critics say that the pull of the NSA's system is so strong that it routinely sweeps up data the agency does not legally have access to.
'I think it is alarming. There seems to be a universal trend toward more surveillance and more surveillance that impacts Americans' privacy without obtaining a warrant,' Neema Singh Guliani, the ACLU's legislative counsel, said.
'This data confirms that there is a lack of acknowledgment that information is being specifically and increasingly mined about Americans for investigations that have little or nothing to do with international terrorism.'
In total, officials searched for the names of 30,355 Americans in communications metadata in 2016 - a 27.5 per cent increase on the previous year.
Metadata includes email addresses and phone numbers, but not the content of the actual communications.
But officials also searched the contents of the communications themselves for the names of 5,288 Americans - compared to just 198 in 2013.
On the up: Searches increased due to Obama easing NSA restrictions in 2011, insiders said. The names were not redacted in thousands of reports passed around government
Those figures don't include searches by the FBI, which are likely to increase the numbers dramatically.
As a result of the Obama administration's searches, thousands of NSA intelligence reports were created and circulated among government offices that had the names of US residents visible.
Usually those names would be redacted and replaced with 'American No. 1' or something similar.
In around half of those cases the identities were initially redacted, but later 'unmasked' by the Obama administration.
Among those that were unmasked were members of Donald Trump's 2016 election campaign team.
In total 3,134 NSA intelligence reports with unredacted names of US residents were created in 2016; 3,354 were created in 2015.
The increase in searches was the direct result of Obama's 2011 decision to loosen restrictions placed on the sharing of information, government sources told Circa.
One, who did not wish to be named, said: 'It’s simply easier for people to make requests.
'And while we have safeguards, there is always concern and vigilance about possible political or prurient motives that go beyond national security concerns.'
Big data: The NSA (pictured) says it only spies on data from foreigners using US infrastructure, but critics say its software pulls in info on US citizens too
Around 20 US officials have the power to unmask a name - something that was once considered a rare act.
The justification need only be that 'the identity of the United States person is necessary to understand foreign intelligence information or assess its importance,' according to a 2011 document related to Obama's easing of intelligence rules.
Officials confirmed that the increase has come as officials became comfortable with the 2011 changes.
Alex Joel, head of the Office of the Director of National Intelligence's Office of Civil Liberties, Privacy, and Transparency, said that the newly released report was a triump of transparency.
'Our goal is to provide relevant information, distilled into an accessible format,' he said.
'This year's report leans forward in that direction, providing significant information beyond what's statutorily required, and reflecting our concerted effort to enhance clarity.'