Researchers at the private RAND Corporation based in Arlington, Virginia, today released an expansive study that points out how little is known about how firearm laws and policies affect gun violence, NPR reports. Only 62 of several thousands of studies demonstrated a causal relationship between gun policies and outcomes such as violent crime, suicide, and accidental gun deaths. The researchers concluded, for instance, that laws preventing children’s access to guns reduce suicides, accidental injuries, and deaths in youths. As part of a larger initiative, of which the new study is a component, RAND has also released a publicly accessible database displaying state firearms laws. A similar database was launched last year by researchers at the Boston University School of Public Health.