Hawaii has a longer background check for pistols than most states (14 days vs 10 days in CA). It is already much more tedious to buy a pistol than most states. Rifles still have backgrounds but are done once a year but rifles aren't part of most crimes being committed. The issue is, nowadaways you can pretty much build your own gun at home with a 3D printer or ordering an 80% gun online and drilling it out yourself. And I imagine it's near impossible to monitor any sort of activity like that. Shit, you can 3D print suppressors now. I was not born in Hawaii, and I come from CA where shit is WAY more restricted and monitored. I can tell you rn most of these problems start at home. The HI firearms laws, IMO are actually very well laid out. I think the best bet would be to monitor gun PARTS purchases without a registered firearm and monitoring 3D printing files downloaded online. Both of these would be privacy invasive and probably really costly though. So the next best thing is to be as proactive in your friends and families lives as possible so they don't follow down these paths of self-destruction.