This is a disturbing book for any liberal who supports private objections of conscience but sees civil disobedience as inappropriate in a democratic society. Professor Brownlee argues eloquently against such privatisation of belief. Although this is a work of philosophy not theology, there are echoes of radical readings of the words of Jesus that ‘he who is not with me is against me’, which inspired movements for the ‘bias for the poor’.

Professor Brownlee identifies four key features of conscientious moral objection: consistency, universality, non-evasion and dialogic effort. By non-evasion she means that objectors must be prepared to be called to account for their actions; dialogic effort requires that they should also be willing to engage society in order to persuade them of their views.

She explores the notion of conscience from the perspective of moral pluralism. This is valuable as she considers the process of conscience but less persuasive as she looks at its content. She talks of the interdependence between cultivating wholesome states such as kindness, compassion, empathy, love, attention, generosity and gratitude combined with self-knowledge. Inevitably she identifies some core values, one of which is that the clarity and open-mindedness of conscience is incompatible with the blind, reckless passion of fanaticism. She characterises the commitment of Nelson Mandela and Aung San Suu Kyi to prioritise their causes over their family lives as heroic: it is arguable that activists should avoid family commitments and that to act as they did was fanatical.

The book makes a strong case for the moral right of civil disobedience, arguing that minorities can have difficulty making themselves heard in a democracy. Democracy as currently practised is a blunt instrument that can be subverted by lobbying and the imbalance of power in society, and decisions made in the name of a people may not reflect their wishes or interests. Civil disobedience has frequently been the precursor to democratic change.

A moral right to civil disobedience does not imply a legal right. However, the author sets out a case for making ‘demands-of-conviction’ or necessity a legal defence. This is a considerable challenge: those who enforce and administer the law may feel great respect for those who have broken it in acts of civil disobedience, but they acknowledge that the law has been broken. Cases are used to show that some judges take civil disobedience very seriously as a threat to the fabric of society, while others will take account of the defendants' motives based on concerns which are not self-serving. Juries have often been unwilling to convict where non-violent action has been used.

I find that there is something contradictory about a law which permits law-breaking. Activities which fell under this category could no longer be called civil disobedience as they would be permitted. It is not clear what the role of public officials should be when activists climb the Shard, the tallest building in the UK, to protest about the fate of the Arctic: should they intervene on behalf of the activists or of the private security companies who might try to prevent them? Freedom of judges and juries to use discretion as they apply the law means that they can engage in the dialogic effort which is a feature of conscientious moral objection. This is an imperfect process as neither judges nor juries accurately reflect public opinion, but it may be the least worst of the possibilities open to a society.

From Rosa Parks to the Greenpeace activists' occupation of the power station at Kingsnorth, from Huckleberry Finn to the Neumanns, a Wisconsin couple who preferred prayer to calling a doctor for their dying child, there is a wealth of contemporary examples of civil disobedience which is considered. Although I question whether it is self-evident that physician-assisted suicide is meritorious or that a law against adultery is wrong, I found it stimulating to engage with the very clearly expressed arguments in this book.

A feature of this book that is noteworthy is the generous manner in which the author acknowledges the ideas of colleagues and an unknown OUP proofreader in her footnotes. The book is an encounter not only with a sharp analytical mind but with a human being who embodies the qualities of conscience that she describes.