Information Commissioner Christopher Graham says issues of national security cannot be allowed to overshadow concerns of legitimate public interest.
He told the Society of Editors' annual conference that he was very concerned by the scale of online surveillance revealed by Edward Snowden, but stopped short of criticising US and UK security agencies.
Graham said security could not trump every consideration and the UK had to find a way to restore confidence in the country’s intelligence agencies, according to the Guardian.
He said he was particularly alarmed by reports that encryption had been compromised and that the "big internet companies have been leaving open the back door for security services".
Graham said while he was advising everyone to use strong passwords and encryption, Snowden’s revelations showed that “encryption is for the birds."
Asked if he was critical of the security agencies responsible, Graham said he was trying to find out more beyond media reports to make a judgement, but that mass online surveillance was not a good idea in principle.
The heads of the UK’s intelligence agencies told parliament’s Intelligence and Security Committee (ISC) on 7 November that Snowden’s revelations had been damaging to UK security and would make their jobs more difficult for years to come.
But Shami Chakrabarti, director of UK civil liberties advocacy group Liberty, praised Snowden and told the conference that the claim was probably an exaggeration because serious adversaries know all about the technological possibilities.
Freedom of information campaigner Heather Brooke also said she supported the publication of the documents leaked by Snowden.
She said the security services believe that if they can spy on everyone at all times, that will keep everyone safe. “A lot of people would argue that is not the case, and that some of the things done in the name of national security are actually incredibly dangerous,” said Brooke.
However, Andrew Vallance, secretary of the Defence Advisory Notice committee, which advises the press when revelations could threaten national security, told the conference he did not approve of Snowden's actions because of the scale of the data involved.
"When you are talking about hundreds of thousands of files you don't know what they contain and therefore what he is doing by stealing these files is to go into the unknown,” he said.
Vallance said he believed the Snowden revelations about the scale of security agency surveillance "will expose us to more dangers".
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