Unfortunately we cannot do scientific trials to verify exactly how much firearms influence deaths in the US: we can't create another US and give them placebo guns. So the best we can do is look at countries of a similar size, or state of development, or culture, or some other criteria, and compare results. I've been to Norway, Israel, and Switzerland, and it's pretty ridiculous to compare them to the US on almost any measure: geography, history, and culture, make them very different. But we can only compare what we've got.
When it comes to these sorts of measures I give weight to neutral bodies like the UN or medical researchers (because guns are, I think, properly thought of as a public health issue). Like this:
- A
2011 UN report says that while there are some countries (e.g., in Africa and Latin America) where per-capita homicides are higher, the US rates are higher than others of a comparable socio-economic levels (though the rate in the US is dropping).
- A
2003 medical paper that says that firearm homicides in the US are 19.5 times higher than in other high-income countries.
- A
2006 medical paper indicating how gun deaths dropped in Australia when gun laws were tightened here.
We can each cherry-pick stats that appear to support different arguments, but if you pile up all the research for and against the idea that gun deaths in the US are a disproportionate problem, we'll find that the "for" pile is much bigger. That's science.