The fulfillment of the promises of American democracy are directly related to the role and presence of civil liberties. From the time of its founding, the Framers of the Constitution were concerned that the government present would grow too powerful and would ignore the rights of the individuals, their civil liberties. This is why the Constitution's First Ten Amendments are directly driven by the individual need to possess civil rights, individual freedoms that cannot be taken away by the governing body. The presence of these individual rights operate as a type of shield that cannot be penetrated by the external government and at the same time also allow individuals to feel safe and comfortable in partaking in the democratic construction of their government.
Civil liberties are the backbone of American democratic freedom. The Bill of Rights 1791 (first 10 Amendments) guarantees individual rights that the government cannot violate such as the right to religious and political freedom, the right to a speedy trial with a jury of ones' peers. (read over the Bill of Rights for additional guarantees) In addition, between 1870 and 1971 five additional amendments increased the civil liberties of Americans they include #14 equal protection under the law/federalizes due process #15 male suffrage, #19 female suffrage, #24 abolishing poll taxes, #26 voting age set at 18 years of age. Moreover, many decisions of the Supreme Court have also served to define and expand the role of civil liberties in the U.S., among them Miranda v. Arizona 1966, Gideon v. Wainwright 1963, Tinker v. Des Moines School District 1969. HOWEVER, INDIVIDUAL RIGHTS/FREEDOMS ARE NOT ABSOLUTE meaning that in the U.S. freedom of individual expression walks hand in hand with the security and well being of society. There is always a delicate balance between these powerful perspectives, which is why the protection, definition, and understanding the scope of civil liberties is vital to the success of American democracy.
Civil liberties play a complicated role in American democracy.
Freedom of speech is the basis of our (or any) democracy. It is the right that really makes us democratic because it is the one that allows us to speak our mind.
But the other civil liberties generally go somewhat against democracy (or at least against popular sovereignty). They tell us to treat unpopular people well in many cases. They tell us to give lawyers to poor criminals and they tell us to sort of rein in the police in what they do in investigating defendants. They sometimes tell us that we should allow people to practice "strange" religious beliefs or they tell us not to have organized prayer in schools. All of these are things that are unpopular with the majority but that we are supposed to do because they are civil liberties.
Overall, then, they play a mixed role -- helping us have popular sovereignty, but then taking it away to some extent.