In two key public messages this week, US National Security Agency whistleblower Edward Snowden has outlined the case against mass surveillance and how it can be defeated through greater use of encryption.

Overnight, Snowden made a rare public appearance via videolink to the SXSW technology conference in Texas (pictured). Earlier this week, he gave written testimony, including answers to questions, to a European Union parliamentary inquiry into mass surveillance. His appearance at SXSW, via a series of proxies to hide his location within Russia (officials in US intelligence agencies have openly discussed wanting to kill him), had been opposed by a US congressman who demanded the appearance be stopped.

Some key themes emerge from both Snowden’s testimony to the EU Parliament and last night’s appearance …

Mass surveillance is potentially damaging to national security. Snowden argues that mass surveillance of all internet and telephone communications has not proven useful in thwarting terrorists attacks — both President Barack Obama’s handpicked surveillance review panel and the Privacy and Civil Liberties Oversight Board were unable to find any evidence that data collected by the NSA had been instrumental in stopping attacks. Snowden also argues it undermines security:

“By squandering precious, limited resources on ‘collecting it all,’ we end up with more analysts trying to make sense of harmless political dissent and fewer investigators running down real leads. I believe investing in mass surveillance at the expense of traditional, proven methods can cost lives, and history has shown my concerns are justified.”

Snowden invokes both the so-called “underwear bomber” in 2009 and last year’s Boston Marathon bombing as examples of how US intelligence services were given advance warning of potential terrorists through traditional sources and failed to act.

There was no mechanism for Snowden to raise concerns about the NSA’s illegal surveillance. Snowden argues — contrary to the arguments of critics that he could have gone through “proper channels” rather than going to the press — that existing mechanisms don’t work. He says he approached a number of officials to raise his concerns but was rebuffed or told “not to rock the boat” each time. Moreover, Snowden could not use existing US whistleblowing laws:

“As an employee of a private company rather than a direct employee of the US government, I was not protected by US whistleblower laws, and I would not have been protected from retaliation and legal sanction for revealing classified information about lawbreaking in accordance with the recommended process.”

Misuse of mass surveillance for economic espionage is routine. “Surveillance against specific targets, for unquestionable reasons of national security while respecting human rights, is above reproach,” Snowden told the EU parliamentary committee. “Unfortunately, we’ve seen a growth in untargeted, extremely questionable surveillance for reasons entirely unrelated to national security. Most recently, the Prime Minister of Australia, caught red-handed engaging in the most blatant kind of economic espionage [in fact it was the Rudd government under which this espionage occurred], sought to argue that the price of Indonesian shrimp and clove cigarettes was a ‘security matter'”. Snowden went on to provide a long list of the many examples of “five eyes” spying for economic purposes revealed by the documents he has provided.

Mass surveillance can be defeated. This was perhaps the key message of Snowden’s SXSW appearance. He urged people wanting to know how to thwart standard mass surveillance mechanisms (as opposed to targeted surveillance, which is far more difficult to prevent) to encrypt their hard drives, block commercial tracking software and use anonymisation systems like Tor. Snowden argues that end-to-end encryption still works (despite efforts by the NSA to undermine encryption standards). Another participant, the American Civil Liberties Union’s Chris Soghoian, noted that mass adoption of encryption would dramatically escalate the cost of NSA surveillance to the point where it may no longer be economically feasible.

Tech industry workers have a responsibility to fight the “fire” of mass surveillance. Snowden chose SXSW, he said, in order to directly tell IT sector workers that they had a responsibility to try to address mass surveillance at a technical level, regardless of what the response from policymakers would be at the official level.

On another front, last week there was a development in a story Crikey has long kept tabs on: the prosecution of jailed US journalist, online activist and occasional Crikey contributor Barrett Brown. Last Wednesday, prosecutors dropped many of the charges against Brown, including the one that has drawn the most attention — sharing a link to credit card details obtained from the hacking of the national security think tank Stratfor, which were already publicly available. Brown, whose primary offence was to reveal the extensive links between the US government and the cybersecurity and defence industry, still faces other charges, including threatening a federal officer, that could total 70 years in prison, although that’s down from the 105 he originally faced.

Apropos of not much, Brown’s case features briefly in House of Cards, when hacker Gavin demands Brown’s charges be dropped or, alternatively, reduced. Life imitating art. Brown’s friend and co-author Gregg Housh was a consultant for the show’s second season.

*Bernard Keane is a supporter of and contributor to the Free Barrett Brown campaign