There has to be research regarding the deaths of Americans in relation to population density that prohibits gun possession and carry. Legislate guns based in population density.

Start here:

https://www.bloomberg.com/news/articles/2012-12-14/the-geography-of-u-s-gun-violence

There is a direct relationship between suicide and homicide and liberal gun decisions by the Robert’s Court.

https://en.m.wikipedia.org/wiki/Firearm_death_rates_in_the_United_States_by_state#/media/File%3A1999-_Gun-related_deaths_USA.png

Reference 

https://www.healthdata.org/

Public health standards are not political fodder. They well studied and established. Gun violence has moved into a public health standard and population density is well established as a focus of those standards.

I also find it odd this decision was leveraged as the US Senate is about to vote on gun regulations.