18th Century Origins:
The Democratic-Republican Party was founded in 1792 from a coalition of Antifederalists and other state's rights advocates. In 1796, Thomas Jefferson ran unsuccessfully against Federalist Party candidate John Adams, who would later pass the Sedition Act to bar Jefferson's supporters in the press from criticizing the government. Jefferson crushed Adams in the 1800 election, and the Federalist Party never won another national election.
19th Century Failures:
As slavery began to dominate the national debate, a clear division began to develop between Northern and Southern Democrats. In 1864, the anti-slavery president Abraham Lincoln ran for reelection on a unity ticket with Democrat Andrew Johnson as his VP candidate. After Lincoln's assassination, Johnson rose to power and attempted to block progressive post-slavery civil rights reform. The Democratic Party of the late 19th century was, for all intents and purposes, the anti-civil rights party of its time--a way of accommodating Southern Democrats who still supported slavery.
20th Century Redemption:
Over time, the national Democratic Party began to become more progressive on civil rights issues as the Republican Party, having achieved its initial objective of abolishing slavery, drifted. In 1948, the Democratic Party surpassed the Republican Party on civil rights issues when President Harry Truman added a civil rights plank to the platform. Southern Democrats, who made up the bulk of the national segregationist movement, were ultimately defeated with the passage of the Civil Rights Act of 1964. Since that time, Southern Democrats have more or less achieved parity with the national party on civil rights issues.
Today, the national Democratic Party is vastly superior to the national Republican Party on issues pertaining to affirmative action, civil rights lawsuits, reapportionment, and active desegregation. It also receives much greater support, on average, from racial and ethnic minority groups than does the Republican Party, and is subsequently more accountable to minority voters in pursuing its agenda. The majority of non-white elected officials are Democrats.
Gender and Sexuality:
The national Democratic Party is more progressive than the Republican Party on gender and sexuality issues, but this is to a great extent only reflective of where the party's strongest bases of support lie--in the progressive Northeast for Democrats, and in the conservative South for Republicans. For this reason, party differences on these issues tend to be more visible on the national level; it is customary (for example) to have a pro-choice Democrat and anti-abortion Republican on the national ticket, but in California or Mississippi both parties' candidates are likely to identify as one or the other.
The First Amendment:
Views on church-state issues also tend to be informed more by regional than partisan concerns. While most advocates of looser church-state separation tend to be Republicans, there is more of a correlation by region than there is by party. Northern Republicans, such as the agnostic Senator Arlen Specter (R-PA), can be as secular as Northern Democrats. On free speech issues, the national Democratic Party tends to support problematic political advertising restrictions but trends slightly better on other censorship-related issues.
The Second Amendment:
The Democratic Party tends to be the party of gun control, though in this instance, as in others, the correlation has more to do with region than with party. Governor Bill Richardson (D-NM), for example, boasts an A+ rating from the NRA--higher than any of the Republican frontrunners--while former New York mayor Rudy Giuliani's record on gun rights, despite his party affiliation, is more troubling. Still, on average, the Democratic Party falls short on Second Amendment issues.
One of the facts often overlooked by critics of the Supreme Court is that the notorious Kelo v. New London (2005) ruling was a 5-4 majority made up of liberal and moderate justices. Despite the Democratic Party's strengths in other areas pertaining to civil rights, the party tends to rank second to Republicans on preventing the government from reclaiming "blighted" property against the owners' wishes for economic development purposes.
Rights of the Accused:
"Law and order" issues no longer define party differences to the degree that they once did, but the national Democratic Party is slightly better than the national Republican Party with respect to protecting the rights of the accused and imprisoned. There are few in either party who favor abolishing the death penalty, but most of those few are Democrats.
The Bottom Line:
The Democratic Party is not the party of civil liberties--there is no party of civil liberties--but it trends much better than the Republican Party on most social issues. While differences among individual candidates and differences in regional identity are more reliable indicators of civil liberties perspectives than party affiliation alone, voters concerned about civil rights, feminism, and LGBT rights are usually (but not always) better off voting Democratic in national elections. This is a function of the fact that the Democratic Party is more popular among, and therefore more accountable to, a voter and donor base that includes significant urban, Northern, west coast, minority, female, and LGBT constituencies. Because local constituencies tend to be more homogenized, there may or may not be any advantage to voting Democratic on the basis of these issues in state and local elections.