Unjust laws and unjust governmental systems are a common theme in Henry David Thoreau's Civil Disobedience and Martin Luther King's Letter From A Birmingham Jail. In Civil Disobedience Thoreau clarifies that following an unjust law is a violation of ones conscience. Also, if a person is faced with an unjust law they should not only disobey it but also strive to somehow change it. In King's Letter From a Birmingham Jail he outlines the reasons for the need of the demonstrations in Birmingham. King notes that civil disobedience is necessary for the case of the city of Birmingham. .
The most obvious influence on King from Thoreau's writing is King's unwillingness to stand back and watch injustice. Action must be taken and the person must be willing to face the full consequences. King believes, "one has a moral responsibility to disobey unjust laws."(1233) While Thoreau states, " if it is of such a nature that it requires you to be the agent of injustice to another, then, I say, break the law."(1222) This is a direct correlation between these two works. .
King evolves Thoreau's idea on not waiting until a person maintains a large majority to change a law. Instead of acting immediately King gathers a large quantity of people to put his point across to the city leaders of Birmingham. An onslaught of activism by a large number of people causes the city to stop ignoring the issue of injustice and address it. Thoreau did not believe heavily in using the governmental system to change the laws. However, King knew that this was the only way to make true permanent progress. So King forced the system to see the plight and take actions to correct it. .
Thoreau's essay was written while two wars raged in America; the Mexican American war and the war of slavery. African Americans were struggling to make their largest leap of freedom in America. Thoreau served a very brief jail sentence for refusing to pay his taxes, which he believed was an injustice.