A representative may pass laws on anything not permitted in the Constitution.
The Second Amendment is one expressly permitted activity. But, since the representatives have not stated that the states will follow the Second Amendment, the only amendment by the way, the states continue to pass laws on guns. I add this second paragraph only as further clarification of what I am talking about.
If the power is granted to the State via its Constitution.
...thanks to people who found it easier to rely upon government force to have their wishes granted than to rely on their own powers of self-determination and self-reliance. As long as people are human, there will be no utopia and EVERYBODY needs to understand that NOBODY can always have things their way. People who smoke realize that they cannont smoke where ever they wish and you (non-smokers) need to realize the same thing and quite whining and looking to government to fight your battles and make your decisions for you. Anyone remember prohibition? This is, in MHO, the reason the nico-nazis don't call for an outright outlawing of all smoking - what the state "only" regulates, it can tax - and whatever the 'state' can convince the sheople is bad for them is subject to even heavier taxation (sin? taxes anyone?). The entire smoking vs. non-smoking dog and pony show is nothing more than a means to divide and conquer on the road to more power over our daily lives. Sadly, most of the anti-smoking folks haven't figured this out yet (and won't until it's too late).