The point is there isn't just a correlation being noted. The research supports various reasons why that correlation is best explained by the easy accessibility of a very lethal weapon - i.e. a gun.
I don't think it's possible to do what you suggest and prove "causality" but the problem with your objection is there must be something about gun owners (besides having a gun) that makes them uniquely more likely to kill themselves. Are they more impulsive, less stable, more violent, care less about the loved ones they leave behind, more unlikely to seek mental health or other services? What factor unique to gun OWNERS, but unrelated to the easy access to guns, would explain the results of a couple dozen studies that show gun owners at a FAR greater risk of suicide?
OK, here's a rundown of many studies on the issue: Suicide | Harvard Injury Control Research Center | Harvard T.H. Chan School of Public HealthYou mention controlling for data points, yet every study I've seen - every one - makes a weak causal argument in spite of controlling for almost no variables. Take the Harvard Study from 2008. As a quick example, that study compares suicides and gun ownership by state. Wyoming is given as an example of high gun ownership, and the correlation is made between that state and other states with low gun ownership rates and lower suicide rates. But what didn't the study control for? Rural vs urban. Mean vs median income. Male to female ratio imbalance. Divorce, Family, and Friend Of The Court practices. Mean age vs age of the suicide. Terminal illness (often a given reason for suicide). Average hours of sunlight. Percentage of the population on SSRIs. Average number of children. Prevalent religion and religious attitudes. Find me a study that even attempts to isolate variables, and I will gladly take a look at it.
And from the summaries are some of the controls in the various studies:
- region, unemployment, alcohol consumption and poverty,
- rates of attempted suicide
- divorce, education, unemployment, poverty and urbanization
- lifetime major depression and serious suicidal thoughts
- differences in mental health do not explain why gun owners and their families are at higher risk for completed suicide than non-gun owning families.
This study surveyed 9,000 households. "Respondents with firearms in the home were no more likely to report suicidal thoughts, plans or attempts, but if they had a suicidal plan, it was much more likely to involve firearms. The higher rates of suicide among gun owners and their families cannot be explained by higher rates of suicidal behavior, but can be explained by easy access to a gun."
OK, even you don't believe the suicide rate in Japan has a thing to do with guns and the risk of a successful suicide attempt in the U.S.The US is top of the list for private gun ownership, yet only 30th in suicides per 100,000 citizens. The top of that list? Greenland, which doesn't even show up on the per capita gun ownership list. Second in suicides per 100,000 is Lithuania, ranking 160th in gun ownership. Third is South Korea, ranking 149th in gun ownership. Japan is seventh in suicides yet only 164th per capita in gun ownership. Why is that? If guns cause suicide, shouldn't the US be first on that list as well?