According to Martin Luther King Jr., a just law is a code that aligns with the moral law or the law of God. It uplifts human personality and is applied equally, meaning the majority imposes it on the minority while abiding by it themselves. An unjust law does not align with eternal or natural law. It degrades human personality and reflects inequality, such as when the majority imposes it on the minority without being bound by it themselves.

In my view, this distinction is important because it influences how individuals and societies engage with the law and justice. When people understand the moral basis of law, they question and challenge laws that perpetuate injustice. It helps create legal systems that promote fairness and protect vulnerable groups from oppression by the government or the majority. It also influences politics by shaping policy debates and inspiring movements for social change.

The Civil Rights Act of 1964 is an example of a just law. It prohibits discrimination based on race, color, religion, sex, or national origin. It uplifts human personality by promoting equality and dignity. Exclusionary zoning laws are an example of unjust law in the USA because they restrict certain types of land use in a community to limit racial and economic diversity. These laws include requirements for minimum lot size or house size that make it difficult for low-income residents to live in an area. It is a discriminatory policy tool.