What is the role of the courts in U.S. politics?

Using the vocabulary of the class as your own words respond to the prompt. DO NOT quote nor cite anyone.
What is the role of the courts in U.S. politics? Why is an independent judiciary so important to our democracy? What are civil liberties and how do the courts protect them? What are civil rights and how have the courts expanded them in recent years? How have the rights of the accused changed? Does all this mean we are “more free” than in the past or “less free?”