2.7x: A 1993 study, funded by the federal Centers for Disease Control, found that people in households with guns were 2.7 times more likely to become homicide victims, and 4.8 times more likely to commit suicide, than people without guns. But the study was less significant for its findings than for the backlash it inspired. Via the so-called Dickey amendment in 1996, Congress put a chill on CDC research with implications for gun policy; restrictions on the National Institutes of Health eventually followed.
Experts say the provision has downstream effects, discouraging researchers from studying gun markets and gun violence — and, indeed, from going into gun research in the first place. In the aftermath of mass shootings, such as the one Wednesday in Parkland, Fla., public health experts now lament the dearth of useful information available to them. Former US Representative Jay Dickey eventually reconsidered his support for the measure that bears his name, but Congress did not.