"Stop Big Brother!" - "Prevent the end of free speech!" - "Protect your privacy!"

These are the battle cries of a small group of British civil rights organisations - and a much larger and more vociferous group of Americans - who are fighting to stop government regulation of encryption.

Alarmist words, but these activists say that encryption, which is virtually unknown outside of the technology community, is the key to privacy and liberty in the information age. Their mission: to break down the technical language of encryption - private and public keys, escrow and trusted third parties - and show that only the free use of encryption will protect individuals who communicate online.

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Cyber rights and cyber liberties

While technology should not dictate policy, any policy must protect privacy, the activists say. They question whether governments should have the right to examine private electronic information without the search warrant they need if the information were transmitted on paper.

A so-called key-recovery policy would allow law enforcement agencies access to any encrypted information. Critics say that this would give the government too much power and create temptation for abuse.

"The question is not whether any such interception and access to encryption keys is wrong, but whether it is safe to entrust all future governments in perpetuity with an unprecedented technical capability for mass surveillance," said Yaman Akdeniz, the founder of Cyber-Rights & Cyber-Liberties UK.

The Web's encryption experts warn that this would also set a bad precedent for other countries. In many places, journalists and human rights activists use encryption to protect themselves from repressive governments. A key-escrow policy would make it impossible to keep any information private.

On top of that, encryption activists argue that a key-escrow policy wouldn't work anyway.

Scientific studies show even if such a policy were put in place, the risks and costs would ultimately prove unacceptable because they require extraordinary levels of human trustworthiness. They predict that if encryption is no longer secure, the "bad guys" will no longer use licensed systems and the government would be unable to monitor their targets.