The emergence of COVID-19 has led to numerous controversies over COVID-related knowledge and policy. To counter the perceived threat from doctors and scientists who challenge the official position of governmental and intergovernmental health authorities, some supporters of this orthodoxy have moved to censor those who promote dissenting views. The aim of the present study is to explore the experiences and responses of highly accomplished doctors and research scientists from different countries who have been targets of suppression and/or censorship following their publications and statements in relation to COVID-19 that challenge official views. Our findings point to the central role played by media organizations, and especially by information technology companies, in attempting to stifle debate over COVID-19 policy and measures. In the effort to silence alternative voices, widespread use was made not only of censorship, but of tactics of suppression that damaged the reputations and careers of dissenting doctors and scientists, regardless of their academic or medical status and regardless of their stature prior to expressing a contrary position. In place of open and fair discussion, censorship and suppression of scientific dissent has deleterious and far-reaching implications for medicine, science, and public health.

Supporters of dominant scientific theories sometimes attack competing, less favoured theories in ways that conflict with expectations of proper scientific behaviour, for example by using double standards. To reduce concern about their actions, supporters can use a variety of techniques: cover up the violation of expectations; devalue the competing theory and its advocates; interpret the process as proper; use expert panels, meetings and other formal processes to give a stamp of approval to the dominant view; and intimidate opponents. These are the same five methods used regularly by perpetrators of actions widely seen as unjust, such as violent attacks on peaceful protesters. When these methods fail, the attack can backfire on the attackers. Orthodox scientists’ treatment of the theory that AIDS originated from contaminated polio vaccines used in Africa in the 1950s illustrates how this framework can be applied to science. Opponents of this theory have used all five methods of inhibiting concern about violations of expected scientific behaviour. This analysis shows why supporters of orthodoxy have a tactical advantage over challengers.

It is important for activists to be able to deal skillfully with their emotions, a process we call emotional self‐management. Done both individually and collectively, this can help activists to be more effective and help create the sort of society they believe is desirable. One approach to skillful management of emotions is through the concept of mindfulness, which involves paying attention to one’s state of being. Activists have much to gain by moving from negative emotions to ones such as ‘joyful hope’.

Many publicly debated issues have implications for health, including smoking, pesticides, food additives, seat belts, fluoridation, vaccination and climate change. Campaigners on such issues use a variety of methods, including presenting evidence and arguments, denigrating opponents, lobbying and organising protests. In some cases, campaigners seek to censor opponents, most commonly on the grounds that their views are false and dangerous. To probe rationales for censorship, recent events in the Australian public debate over vaccination are examined. A citizens’ group critical of vaccination has come under heavy attack, with pro-vaccination campaigners and politicians trying to shut down the group and restrict its speech. This case study provides a window into arguments about free speech on scientific controversies with implications for public health. It highlights the tension between the alleged dangers of expressing ideas and the value of open debate in a free society.

Random selection provides a way to overcome some of the usual problems of citizen participation in technological decision making. It offers representativeness with a minimum of bias and susceptibility to vested interests. There are a number of requirements for the effectiveness of the random selection approach, such as that citizens are interested and capable of rational deliberation. A number of recent experiments with policy juries and planning cells are assessed to see how well they satisfy the requirements for the effectiveness of the approach. While random selection shows great promise as a means for involving citizens in technological decision making, there are obstacles to promoting the use of this approach for policy purposes, perhaps especially because it so effectively circumscribes the role of political élites.