Law and morality overlap but are not the same. Most legal systems forbid murder and theft, which are also moral wrongs, but many laws are morally neutral (which side of the road to drive on), and some laws in history have been gravely unjust. This level looks at three questions: what to make of unjust laws, when breaking the law may be justified, and how far law should enforce morality.

Unjust laws

For natural lawyers, a gravely unjust law lacks the full authority of law. For positivists, it is law, but its validity does not settle whether it should be obeyed. After the Second World War, the German legal philosopher Gustav Radbruch, whose earlier work is often read as positivist, proposed what became known as the Radbruch formula: when a statute's injustice reaches an intolerable degree, the statute must give way to justice. German courts later drew on this idea when judging acts done under Nazi and East German laws.

Civil disobedience

In his 1849 essay later known as “Civil Disobedience,” Henry David Thoreau defended refusing to pay taxes to a government that supported slavery. Gandhi and Martin Luther King Jr. turned such refusals into mass movements. In his 1963 Letter from Birmingham Jail, King argued that people have a moral responsibility to disobey unjust laws, but must do so openly, lovingly and with willingness to accept the penalty.

Philosophers usually define civil disobedience as a public, nonviolent, conscientious breach of law aimed at changing a law or policy, with willingness to accept the legal consequences. It differs from conscientious objection, in which a person refuses to take part personally (for example, in military service) without necessarily seeking to change the law, and from revolution, which rejects the legal order as a whole. Critics argue that if everyone broke laws they disliked, the rule of law would collapse, and that democracies offer lawful ways to seek change. Defenders reply that civil disobedience shows respect for law by accepting punishment, and that history vindicated many who used it.

Changing the law lawfully

Law can also change through its own channels. Legislatures can make broad changes that apply to everyone going forward, after public debate, and they answer to voters. Courts change law case by case, by interpreting statutes and constitutions; they can protect unpopular minorities but are criticized when they seem to decide questions better left to voters. Both routes can work together. In Somerset's case (1772), an English court held that an enslaved man could not be forcibly removed from England. The ruling was narrow, and the British Parliament abolished slavery in most of the empire only in 1833.

The Hart-Devlin debate

In 1957 a British government committee, the Wolfenden Report, recommended that private homosexual acts between consenting adults should no longer be crimes, arguing that some private morality is not the law's business. The judge Patrick Devlin replied in a 1959 lecture. He argued that a society is held together by a shared morality and may use the law to protect that morality, much as it protects itself against treason. As a guide, he pointed to the feelings of intolerance, indignation and disgust of the reasonable person.

H. L. A. Hart answered in Law, Liberty and Morality (1963), drawing on John Stuart Mill's harm principle. Mill had written in 1859 that “the only purpose for which power can be rightfully exercised over any member of a civilised community, against his will, is to prevent harm to others.” Hart argued that majority disapproval alone does not justify punishment, that societies survive changes in moral views, and that enforcing popular morality risks the tyranny of the majority. Devlin's defenders say every legal system enforces some shared values. The underlying question of when law may enforce morality applies to many issues, from gambling to drugs.

Worked example: three responses to a curfew

An invented town passes a curfew forbidding anyone under twenty-one from being on the streets after 9 p.m., after a few incidents of vandalism. Many young people feel the law punishes them all for the acts of a few. Consider three responses.

Dana organizes a public evening gathering in the town square. The group notifies the press, stays peaceful, and waits to be cited, explaining that they are breaking the curfew to show that it is unjust. This fits the standard definition of civil disobedience: public, nonviolent, conscientious, aimed at changing the law, and accepting the consequences.

Eli works night shifts at a hospital and quietly keeps going to work, telling his supervisor he cannot in conscience abandon patients. He is not trying to change the law, only to avoid taking part in what he sees as wrong. This is closer to conscientious objection.

Farah takes the lawful routes. She gathers signatures to ask the town council to repeal the curfew, and a lawyer friend files a case arguing that it violates the constitutional right to free movement.

Now run the Hart-Devlin lens. A Devlin-style supporter of the curfew might stress the community's shared sense of order. A Hart-style critic would ask: what harm to others is being prevented, and does the curfew restrict many innocent people to stop a few? The answers depend on facts as well as values, which is why good public debate about law needs both.