Authority is the legitimate use of power by rulers over the individuals they rule. It is a government’s justification for exercising power over the people within its jurisdiction. The people are willing to accept the power of rulers to command them if they perceive that this power has been acquired and used rightfully or legitimately.
When rulers have authority to use power through government, the consequence is political order and stability among the people. When rulers use power without authority, they may be resisted by the ruled, leading either to oppression by rulers over the ruled or to disorder and instability.
In a democracy, the source of authority or legitimacy for government is the consent of the people, who believe that their rulers have the right to exercise certain powers over them. This legitimacy of government in a democracy is based on the people’s election of representatives in the government. If the people believe their rulers have been elected fairly, then they are likely to accept their authority and consent to the government that they control. All the power of military and police forces in a democracy is under the control of civilian authorities accountable to the people at large.
John Patrick, Understanding Democracy, A Hip Pocket Guide