What is authority and how is it related to domination and the law?
Authority, according to Max Weber, is the power which is legitimate, justified and proper. It is generally derived from the official position of a person and the powers are specified on written documents. Other members of a society implicitly agree to follow the authority. For example, the authority of police or a judge.
A law is an explicitly codified norm or rule and usually exists in a written form. Authority is related to law and domination as the difference between the strict authority, which is explicitly codified, and the informal authority, lies in the notion of law.
In a modern democratic state, the laws are created by legislature. They act as a binding force on citizens and, hence, dominate them. This domination works through legitimate power or authority, a large part of which is codified in the law. It requires consent and cooperation on a regular basis to maintain legitimacy.