Comment: This potential invasion of privacy is an affront to a democratic society

You know you're in trouble when the best argument you can come up with is 'think of the children'.

By Nick Pickles 

"Looking at who a suspect talks to can lead the police to other criminals. Whole paedophile rings, criminal conspiracies and terrorist plots can then be smashed. Data like this has already helped lock away murderer Ian Huntley. It helped catch the gangland thugs who gunned down Rhys Jones. Last year, police smashed a major international child pornography website based in Lincolnshire. They then used internet data analysis to find other suspected paedophiles." – Theresa May, 2012

After a Sunday newspaper reported on details of the government's plans to increase its surveillance capacity across a whole new range of communications channels, it took the home secretary two days to come out in defence of her policy.

The government has still not published the full details of what it wants to do. We, the public, are deemed not worthy of knowing how or why the government wants to spy on us. Pressed yesterday, the minister responsible couldn't even say if it would be in the Queen's Speech.

Accordingly, it's impossible to know for certain what the government plans. Indeed, Home Office ministers seem intent on ensuring that we don't find out what they are planning until the last possible moment.

So why the change of heart? In opposition, the Conservatives and Lib Dems rightly pointed out the vast range of problems such a scheme entailed. The proposals were dropped – but not until after some serious bluster.

When a Labour government drops an IT project because of feasibility, privacy and cost concerns – given their track record where IT projects were concerned – it's a fair indicator that all is not well.

Technically, it's far from clear this will actually work. The technology to both obscure and evade surveillance is an important security protection for doing business online and readily available. Processing the data collected will require a processing capability that arguably doesn't exist yet, or is so expensive even one of Gordon Brown's finest 'investment' spread sheets couldn't find the funding.

Furthermore, this will not be law for the Olympics. An essential, must-have, sky-will-fall-in without it proposal has sat on the shelf for two years, having to wait in line behind a referendum on the voting system for parliamentary time.

It is absurd to say that, because the government isn't reading our emails, privacy is not an issue. You're not required to say who you are when sending a letter (yet, at least) so why should a different rule apply to an email?

Freedom of speech and association requires the ability to communicate in private. Logging who you are talking to, when, for how long and where is the kind of monitoring that chills freedoms, not defends them.

Such collection will be prone to abuse, incur huge costs for service providers and it is far from clear it will actually improve public safety. When you're looking for a needle in a hay-stack, you don't make the search easier by adding more hay.

The desire of the state to pry into every aspect of our lives – without any suspicion, let alone evidence – of wrongdoing is not a healthy basis for democratic society. Nor is ministers reaching for hysterical arguments about paedophiles the best way to support policy.

Nick Pickles is the director of Big Brother Watch, the campaign group formed to fight intrusions on privacy and to protect civil liberties.

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