Like all legislation, if they propose legislation they should make sure that it would have prevented the incident if it had been in place before the incident .
Pardon me, but that's an unworkable standard. Acts such as murder, rape, robbery, embezzlement are all against the law, yet people still commit those crimes regardless -- does that mean we shouldn't have laws making those acts illegal in the first place?
Laws are deterrent, not preventive, since it's unreasonable to expect any law to guarantee it will prevent a determined enough person from breaking it. Even if you're willing to go to Orwellian lengths, you're never going to actually guarantee some one person won't commit a criminal act -- the best you can do is make the punishment harsh enough so as to be a deterrent in most cases, or put enough logistical road blocks in the way such that they, too, become a deterrent (or, ideally, both).
The so called assault weapon ban sure ddnt,
Inconclusive, actually. Since the ban lasted only ten years, in a society so saturated with guns, that wasn't enough time to gather any really meaningful data one way or another.
Plus, how do you gather data on a person intending a crime, but who actually was deterred by a law and its consequences and walked away? There's just no way of tallying that kind of thing ...
People shouldn't propose legislation that will cut off millions of people' freedom on a knee jerk response to a tragedy that wouldn't have been prevented if the legislation had been in place before.
A few points:
a) This kind of thing has happened often enough that I'd think the suggestion of reviewing our gun control laws as a result is hardly a "knee jerk" response at this point ...
b) Nobody is suggesting repealing the 2nd Amendment (although that could be an interesting national dialogue). And if, say, passing a law limiting ammo clips to single-digit rounds is "cutting off millions of people's freedom," then perhaps it's time to also have a conversation about what we actually mean by "freedom" these days ... And,
c) With the person dead, it's unknowable wether a particular law would have prevented him from committing this specific act. Again, such a standard is untenable since the data we have available isn't that definitive or fine-grained -- the best we can do is find trends in crime rates and whatnot, and even that can be a bit fuzzy. All of which doesn't mean we should just throw up our hands and not examine how we as a society should be addressing this issue.