Today's Ruling...(highlights)

Held: 1. The Second Amendment protects an individual right to possess a firearm unconnected with service in a militia, and to use that arm for traditionally lawful purposes, such as self-defense within the home.

(a) The Amendment’s prefatory clause announces a purpose, but does not limit or expand the scope of the second part, the operative clause. The operative clause’s text and history demonstrate that it connotes an individual right to keep and bear arms.

(c) The Court’s interpretation is confirmed by analogous armsbearing rights in state constitutions that preceded and immediately followed the Second Amendment.

3. The handgun ban and the trigger-lock requirement (as applied to self-defense) violate the Second Amendment. The District’s total ban on handgun possession in the home amounts to a prohibition on an entire class of “arms” that Americans overwhelmingly choose for the lawful purpose of self-defense. Under any of the standards of scrutiny the Court has applied to enumerated constitutional rights, this prohibition—in the place where the importance of the lawful defense of self, family, and property is most acute—would fail constitutional muster. Similarly, the requirement that any lawful firearm in the home be disassembled or bound by a trigger lock makes it impossible for citizens to use arms for the core lawful purpose of self-defense and is hence unconstitutional.

I am not sure how many states or cities require trigger locks, but IIRC there is a Massachusetts law requiring this. Such a law would now be considered unconstitutional.

Here is the whole thing.