Final answer:
The Supreme Court cases District of Columbia v. Heller and McDonald v. Chicago both reinforced Second Amendment rights by first finding a D.C. gun ban unconstitutional and then extending that individual right protection against state infringement through the Fourteenth Amendment.
Step-by-step explanation:
The Supreme Court cases of District of Columbia v. Heller and McDonald v. Chicago both dealt with the issue of Second Amendment rights related to firearm ownership. In District of Columbia v. Heller, the Court held that a D.C. handgun ban violated the Second Amendment because it infringed on an individual's right to keep and bear arms for lawful purposes such as self-defense within the home. This decision was significant because it applied only to federal enclaves like D.C., as it is under federal jurisdiction. However, the legal landscape was further shaped by McDonald v. Chicago, where plaintiffs challenged gun bans in Chicago based on the precedent set in Heller. The Supreme Court extended the Heller ruling by incorporating the Second Amendment through the Fourteenth Amendment to apply to the states, meaning state gun control laws could now also potentially violate the Second Amendment.
This series of events led to a similar holding in both cases: individual Second Amendment rights are protected against infringement by both federal and state governments. However, the Court also indicated in later rulings that the Second Amendment rights are not absolute and certain gun control measures may still be permissible.