A Birmingham academic has written a guide to beat spymasters at GCHQ, saying we are close to living in a “surveillance state”.

Tom Chothia from the University of Birmingham said he was concerned over revelations that the intelligence agency was using technology to view and store private webcam images.

And Mr Chothia, a lecturer in computer science, posted an article entitled: “How to protect yourself when GCHQ goes for your webcam” to help worried users.

The revelations about the methods used by the spy centre have caused widespread outrage after leaks of intelligence documents by ex-US security contractor Edward Snowden.

Deputy Prime Minister Nick Clegg this week called for a “significant revamp” of the oversight of the data-gathering activities of the intelligences services.

Mr Chothia said: “GCHQ protects us best when it works within a clear legal framework and with the full support of the public.

“I’m sure members of GCHQ would support this; they would be the last people to want completely unrestricted access to all of our data at all times.

“In the UK we have laws that aim to allow GCHQ unrestricted access to our metadata (i.e. who we talk to and when) and, when it has a good reason, access to the content of the messages we send.

Tom Chothia Lecturer in Computer Security at the University of Birmingham
Tom Chothia Lecturer in Computer Security at the University of Birmingham

“However, in this case it seems that some members of GCHQ viewed intimate images of webcam users who were not intelligence targets. I doubt that this is what the authors of our laws intended. So, in my view, we need to think very carefully about the laws we currently have in the UK and if they strike the right balance between privacy and security for the digital age.

“When we use chat products with encryption we keep our images safe from hackers, a safer Internet benefits everyone and I would certainly recommend that we use encryption whenever possible.”

In his article, which was published on the academic website The Conversation, he said: “News that government intelligence agency GCHQ has been intercepting and storing webcam images from 1.8 million users of Yahoo’s chat service under the codename Optic Nerve is a reminder of how close we are to living in a surveillance state. Webcams, embedded in laptops and sitting on top of monitors, have become a standard piece of computing equipment, but it has now become clear that these can be used against us.”

To try and avoid being targeted, Mr Chothia recommends that anyone using chat products should chose those with encryption wherever possible, although he warns that with the help of the companies providing the services, such as Apple and Google, GCHQ would still be able to access the data.

He said: “The best way to protect the privacy of your webcam chats is to make sure that they are encrypted. Yahoo’s web chat server was based on its Yahoo Messenger system, which dates back to the nineties. This legacy system has never supported encryption and it was this weakness that made it possible for GCHQ to harvest personal images on such a large scale.”

On Google Talk, Mr Chothia described it as a “better option”, as it encrypts data between the user and its servers, and then re-encrypts it when it is sent to another user. However the user is reliant on Google keeping the images secret. Best protection was said to be provided on Apple’s Facetime which boasts full encryption of images.

GCHQ Headquarters
GCHQ Headquarters

Mr Chothia added: “The best option of all would be for some discussion about how we strike the balance between personal privacy and national or international security. According to the latest leaked documents, GCHQ staff have been viewing intimate images of webcam users who were not intelligence targets.

“This would be illegal if a hacker had done it but it is likely that GCHQ’s actions are legal under the UK Regulation of Investigatory Powers Act.

Even so, it seems doubtful that the mass collection of intimate images of innocent people was something that the authors of this law intended. We need to think about whether we can update this and other laws to better suit the digital age. That means better suited to everyone, rather than just GCHQ.”

This week Mr Clegg set out aw series of reforms he is pushing his Tory coalition partners to back, including annual reports on requests made to internet and telephone providers.

Shadow home secretary Yvette Cooper has called on the Government to engage in a serious public debate about issues surrounding privacy, data and the private sector. Mr Clegg called for the swift implementation of a series of changes that “together represent a significant revamp of the oversight applied to our intelligence agencies”.