It's been a deadly week of gun-fuelled hate crimes in America.

On Saturday, a gunman murdered 11 people at a Pittsburgh synagogue and injured six others, telling a SWAT officer that he wanted "all Jews to die."

Before that, a white man rolled into a Kentucky grocery store last Wednesday and gunned down two unsuspecting black shoppers before reportedly telling a witness "whites don't kill whites."

The gun problem in America goes beyond these high-profile mass shootings, which only account for about one half of one per cent of annual gun deaths in the US, according to a 2018 study from the non-partisan Rand Corporation.

Over the course of a lifetime, your odds of being murdered by someone with a gun in the US are strikingly high: about 1 in 315. That means you're more likely to get shot and die in America than you are to get killed riding in a car or even choking on food.

One reason it's tough for Americans to decide what to do about the country's gun crisis boils down to a simple, scientific truth: it's impossible to know what works if you don't study it.

Non-partisan researchers at the Rand Corporation spent two years poring over the available data on gun policies in the US, trying to uncover new evidence on what constitutes effective gun legislation.

They looked at thousands of studies, attempting to evaluate how effective 13 different gun policies – including background checks, conceal carry laws, and minimum age requirements – have been.

But they had trouble coming up with any science-backed, evidence-based strategies that might help reduce violent gun death rates in the US.

Background checks might decrease suicide rates, but the evidence isn't clear. Conceal-carry laws may increase violent crime, but the researchers couldn't say that with certainty.

All they could say for sure was that rules requiring people to keep their guns locked and safely out of the hands of children help reduce firearm self-injuries in kids, including suicides and other deaths.

But when it comes to determining whether or not the same holds true for adults, the researchers didn't have enough evidence to say conclusively one way or the other.

Why don't we collect enough data on gun violence?

The Centres for Disease Control and Prevention (CDC) used to collect data on gun ownership and use on a state-by-state level.

But the Dickey Amendment, pushed by the National Rifle Association (NRA) and passed by Congress in 1996, almost zeroed-out the CDC's gun violence research budget. It also now forbids the CDC from "advocating or promoting gun control".

Since 2003, when the Tiahrt Amendment was passed, the US Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) has also been barred from releasing any gun trace data it collects.

That would be invaluable information for researchers studying how criminals buy their weapons and how guns travel across state lines.

The NRA claims that Tiahrt protects gun dealers from lawsuits, but mayors and police departments who are trying to crack down on illegal guns want the amendment scrapped.

Here's how much money the US spends studying gun violence in America today, compared to other leading causes of death in the country:

gun violence graph

"Collecting more and stronger evidence about the true effects of laws is a necessary and promising step toward building greater consensus around effective gun policy." Rand project lead and behavioural scientist Andrew Morral said in a statement.

To that end, the Rand team is now pressing the federal government to spend more cash on gun control research, hoping that politicians will take the opportunity to reverse decades of Congressional bans that leave scientists in the dark.

This article was originally published by Business Insider.

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