The United Nations has defended the use of strong encryption software as vital to protecting free speech around the globe, in a new report which clashes with recent statements from London and Washington.

The report was compiled by David Kaye, UN special rapporteur on the promotion and protection of the right to freedom of opinion and expression.

It argues that many journalists, activists, artists and regular citizens today use encryption and anonymity tools to protect their privacy; to empower them to browse, develop and share opinions without interference; and to otherwise exercise their right to freedom of opinion and expression.

However, financial crime, bullying, illegal drug dealing, child porn, terrorism and more are also made possible via these tools.

As a result, the report attempts to examine to what extent governments can restrict anonymity and encryption.

It explains that any restrictions placed on these concepts should be “strictly limited according to principles of legality, necessity, proportionality and legitimacy in objective.”

It concludes:

“States should promote strong encryption and anonymity. National laws should recognize that individuals are free to protect the privacy of their digital communications by using encryption technology and tools that allow anonymity online. Legislation and regulations protecting human rights defenders and journalists should also include provisions enabling access and providing support to use the technologies to secure their communications.”

The authorities in member countries should “avoid all measures that weaken the security that individuals may enjoy online, such as backdoors, weak encryption standards and key escrows,” the report argues.

However, the UN does admit that in some circumstances law enforcement should be able to “restrict” anonymity and encryption, but only on a case-by-case basis.

Each of these cases must “meet the requirements of legality, necessity, proportionality and legitimacy in objective, require court orders for any specific limitation, and promote security and privacy online through public education.”

The report is somewhat at odds with recent remarks made by senior officials on both sides of the Atlantic.

US attorney general, Eric Holder, FBI director, James Comey, and Homeland Security (DHS) secretary Jeh Johnson have all argued for greater restrictions on encryption, claiming that it helps hide criminal activity from law enforcers.

UK prime minister, David Cameron, went even further, arguing that in extremis, it should be possible for law enforcers to access and read strongly encrypted communications.

His remarks have been widely criticized by cybersecurity experts, with many claiming that this would basically require backdoors to be inserted by vendors like Apple and Google into their products.

If this were to happen, cyber-criminals would eventually manage to get hold of the same backdoors, dealing a blow to corporate security efforts by effectively exposing all users to snooping.