Newswise — Fifteen states plus the District of Columbia strengthened their gun laws in the year following the Newtown school shooting, accounting for roughly half (44 percent) of the U.S. population.

This finding is one of many in a new publication from the Johns Hopkins press, Updated Evidence and Policy Developments on Reducing Gun Violence in America.

The publication is a one-year update to Reducing Gun Violence in America: Informing Policy with Evidence and Analysis, and provides new data, research and developments on many gun policy topics, such as background checks, handgun purchaser licensing and personalized or smart guns. Other critical issues addressed include ways to curtail gun trafficking and expanding firearm prohibitions for domestic violence offenders, persons convicted of violent crimes, substance abusers and those determined to be a danger to others or themselves as a result of mental illness. Chapters were written by the leading experts in gun policy and research.

“Contrary to popular belief, the tragic loss of life at Sandy Hook elementary school led to a number of significant policy developments, particularly stronger gun laws at the state level,” said Daniel Webster, ScD, MPH, director of the Johns Hopkins Center for Gun Policy and Research, and an editor and author of Reducing Gun Violence in America: Informing Policy with Evidence and Analysis and the new updated version.

“While Congress failed to pass a background check bill, eight of the fifteen states that strengthened their gun laws made fairly substantial changes, including Colorado, Delaware, Illinois and New York, which expanded background check requirements for gun sales, and Maryland, which enacted handgun purchaser licensing with fingerprinting of applicants.”

Noteworthy advances in 2013 chronicled in Updated Evidence and Policy Developments on Reducing Gun Violence in America include measures to improve the capacity of the U.S. Department of Justice to enforce federal laws against gun traffickers, and legislation at the state level to reduce intimate partner violence offenders’ access to firearms.

“States such as Utah and Minnesota were wise to adopt policies designed to restrict or further restrict batterers’ access to guns, given what we know from research about the lifesaving benefits of laws that prohibit persons under restraining orders for domestic violence from having a firearm,” said April Zeoli, PhD, author of the chapter on intimate partner violence and an assistant professor in the School of Criminal Justice at Michigan State University.

“In fact, a key takeaway of this publication is that a data-driven approach to firearms policy whereby individuals with a history of violence or other seriously dangerous behavior should be disqualified, even temporarily, from owning or purchasing firearms will reduce gun violence.”

The publication cites research from Johns Hopkins that focused on individuals who had been incarcerated for crimes involving firearms in the weakest states for legal gun ownership. The researchers found close to sixty percent (59.7%) of the subjects were not subject to firearm prohibitions when they committed their crimes; this would have been reduced by nearly half had the states (or the federal government) enacted additional prohibitions such as establishing 21 as a minimum legal age for possessing a handgun and prohibiting serious juvenile offenders, violent misdemeanants, and those with multiple drug- or alcohol-related convictions from possessing firearms.

“A data-driven approach should also extend to the way we think about mental illness and gun violence,” said Jeffrey Swanson, PhD, a professor in psychiatry and behavioral sciences at Duke University who co-authored a chapter on mental illness and gun policy.

“Policies should recognize that a history of any kind of violence—particularly with court involvement—is a better predictor of future gun violence than mental health history.”Earlier this year, The Consortium for Risk-Based Firearms Policy, a consortium of the nation's leading experts in gun violence prevention and mental health law and policy, of which Dr. Swanson and several other chapter authors are members, crafted state and federal policy recommendations calling for temporary restrictions of up to five years on the purchase and possession of firearms by individuals convicted of violent misdemeanors, domestic violence, or more than one drug or alcohol conviction within a certain period.

“These recommendations are very much in line with what the vast majority of the American public -- including gun owners -- want in terms of keeping guns away from high-risk individuals,” said Jon Vernick, JD, MPH, co-director of the Johns Hopkins Center for Gun Policy and Research, and an editor and author of Updated Evidence and Policy Developments on Reducing Gun Violence in America.

New research in Updated Evidence and Policy Developments from author Dr. Garen Wintemute, MD, MPH, Director of the UC Davis Violence Prevention Research Program finds gun dealers, too, support policies to broaden denial criteria for owning guns. He reports on a survey he led of federally licensed firearm retailers in 43 states: Nine of ten retailers (90.1%) supported a firearms prohibition for persons with alcohol abuse and repeated cases of alcohol-related violence; seven in ten (70.7%) favored prohibiting sales to people who have been convicted of multiple DUI convictions.

“Unfortunately, the handful of states that have listened to their constituents and enacted laws intended to prevent high-risk individuals from accessing guns are undermined by the gaping hole in Federal law which gives criminals and other high-risk groups the option of going to private sellers at gun shows, on the Internet, or elsewhere to buy guns,” said Wintemute.

Federal law requires that individuals seeking to buy a gun at a licensed dealer pass a background check to prevent criminals and other dangerous people from purchasing firearms. But federal law and laws in most states exempt these regulations when the firearm seller is unlicensed.

In 2013, U.S. Senators Joe Manchin and Pat Toomey put forth a bill expanding criminal background checks to gun shows and Internet sales.

For Updated Evidence and Policy Developments, Johns Hopkins researcher Emma McGinty and colleagues examined public opinion data and found that in states where one Senator voted against the Manchin-Toomey federal background check bill, 88 percent of respondents support universal background checks. In states where both Senators voted against the bill, 87 percent support the policy.

“Mobilizing and increasing the political participation of gun owners who support policies like universal background checks is a critical next step,” said Webster. “Right now, politicians who are influenced by the gun lobby are not being responsive to the majority of their gun-owning constituents.”

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