“First they came for the Socialists, and I didn't speak up, because I wasn't a Socialist... Then they came for the Jews, and I didn't speak up, because I wasn't a Jew. Then they came for me, and there was no one left to speak up for me.” Martin Niemöller's poem, criticizing the inaction of German intellectuals in the face of the rise of the Nazis, serves as a powerful analogy for why scientists should be concerned by abuses of academic freedom, wherever they occur.

Most readers of Nature take it for granted that they can travel to work each day, free to enquire, express opinions and criticize government policy, without fear of intimidation or reprisals — let alone imprisonment or torture. Sadly, these freedoms can only be dreamt of in many countries of the world, where academics must live with, and often suffer directly, human-rights abuses. Their plight is our business.

But beyond humanitarian grounds, in this interconnected world we are engaged in a battle of ideas, and the failure to defend any abuse of academic freedom undermines the very principles that guarantee the rights we currently enjoy. Oppressive regimes typically stifle enquiry, as critical minds will inevitably also scrutinize their leaders. Enquiry is further undermined in such environments by the award of senior academic posts to the politically loyal rather than the competent, and the selection of policies or actions that suit governments' agendas, regardless of the scientific evidence.

That latter characteristic is central to the trial of six medical workers — five Bulgarian nurses and a Palestinian doctor — currently facing the death penalty in Libya on charges of infecting hundreds of children with HIV (see page 612). The real evidence has been purged from the trial. So it is encouraging that several major scientific bodies have now weighed in to demand that the court hears the scientific facts.

Tripoli may seem far away, but knowledge and academic freedom are central planks in many other struggles across the world for more open, democratic societies. Academics and universities are often hotbeds of such reform movements, and every year hundreds of academics worldwide consequently face threats, or worse. It is important that we do not forget them.

Many learned societies, including the American Physical Society and the American Chemical Society, as well as several scientific academies, have human-rights committees that play an active role in defending individuals at risk. This diverse range, and the mechanism whereby one body takes the lead on a case where it knows the community, is an effective way of dividing up resources. Cases are many, and no one community can give sustained attention to them all.

Most societies' human-rights activities are run on a shoestring by volunteers. The US National Academies' Committee on Human Rights is among the most effective, and has a full-time secretariat. Yet it runs on a budget of just $0.5 million a year, most of it contributed by philanthropies. Scientists must find the means to better fund and professionalize such activities.

Often these committees use political contacts and letter-writing campaigns to try to influence the outcome of particular cases. At the very least, this serves to remind perpetrators that they are under international scrutiny. Scientists who have been freed testify that, although difficult to pin down, such support is crucial. All scientists can contribute, by making themselves aware of current cases of human-rights abuses and by lending their support to campaigns against them.