I'm shocked at just how ridiculous D.C's arguments are in their brief. One could write pages refuting every unsubstantiated premise, every misrepresentation and downright fear-mongering you find written here. I had a post going but their brief is so packed full of BS I didn't finish.
One thing that stood out to me was D.C.'s claim that since Heller is 66 years old he's not part of the militia. I doubt the justices will take kindly to being told that they are too old to be part of the militia.
Read towards the end where they attempt to explain how a functional long-gun ban and all-out handgun ban are "reasonable restrictions." They also say that handguns have no militia use. That must be why the U.S. military issues Beretta 92's (M9's) with "evil high-capacity clips."