Key Decisions

The following is a partial list of landmark court decisions in the United States. Landmark decisions establish a significant new legal principle or concept or otherwise substantially change the interpretation of existing law.

Participate in interactive landmark Supreme Court cases that have shaped history and have an impact on law-abiding citizens today.

The court decided in Glossip v. Gross that states may use a drug linked to apparently botched executions to carry out death sentences.

Read about landmark cases that have changed history, from Marbury v. Madison to the challenge to Obamacare.

In Dred Scott v. Sanford, Dred Scott, a slave in Missouri, sued for his freedom on the grounds that he had lived for a time in a "free" territory. The Court ruled against him, saying that under the Constitution, he was his master's property. At the same time, the Court also ruled that the Missouri Compromise (1821) -- under which Missouri was admitted to the union as a slave state, Maine as a free state and slavery prohibited in the territory that later became Kansas and Nebraska - was unconstitutional because it deprived slaveowners of their property.

The Supreme Court's 2014-2015 term included a historic ruling on the legality of same-sex marriage and upheld a key part of President Obama's health care law. Here's a look at how justices voted in 13 key cases this term.

Street Law, Inc. developed land mark cases in 2002, with funding from the Supreme Court Historical Society to provide teachers with a full range of resources and activities to support the teaching of landmark Supreme Court cases.

Following is a list of U.S. Supreme Court decisions involving civil rights and discrimination.

These are the three cases that could affect millions of Americans' lives.

See CNN's Top U.S. Supreme Court Decisions Fast Facts for a look at cases decided by SCOTUS, including on same-sex marriage and the Affordable Care Act.