This post is a handy reference for the technical reasons why requiring 3D printers to screen for gun parts is not an effective way to reduce guns or gun violence. I am publishing it on the occasion of both New York and Washington State introducing bills to require this type of screening. In addition to a topic that I have been researching for over a decade, the question of how to know if a 3D printer is printing a gun part is something I spent a lot of time working on while overseeing trust and safety at a large 3D printing service provider.
This post is not about debating the larger legitimacy of gun control. It assumes that gun control is a reasonable and legitimate action of governments in order to focus on the technical reasons why requiring 3D printers to identify and refuse to print gun parts does not work.