As part of a campus-wide, week-long ‘Teach-In,’ Penn LDI and the Penn Injury Science Center are co-hosting a session on Firearm Violence: Science, Policy, & Politics. Given the contentiousness of the issue, it perhaps should be subtitled, “Can we just talk about this?”

In preparation for the event, and for those who can’t attend, we asked our experts for a “reading list” of studies that focus on the factors contributing to and the effects of firearm violence in the United States. Together, they represent a good, quick overview of the evidence base that can inform firearm policy. Or at least the conversation about it.

First, the basics. Firearm violence in the United States claimed the lives of 38,658 people in 2016. This review article describes the epidemiology of firearm violence.  It stresses five main points:

1. The overall fatality rate from firearm violence has not changed in more than a decade.
2. Suicide is the most common form of fatal firearm violence and is increasing. Homicide is decreasing.
3. Homicide risk is concentrated among Black males through much of the life span. Mortality rates from firearm violence are very high and unchanged in this group.
4. Suicide risk is highest among White males beginning in adolescence. 
5. Compared to other industrialized nations, the United States has low rates of assaultive violence but uniquely high mortality rates from firearm homicide and suicide.

► READ: The Epidemiology of Firearm Violence in the Twenty-First Century United States, Annual Review of Public Health Vol. 36:5-19, March 2015. 

Let’s remember that deaths are not the only harm to be considered in firearm policy. More than 70,000 non-fatal firearm injuries occur each year in the United States, leaving lasting physical and emotional scars. Recent studies by Therese Richmond, CRNP, PhD and colleagues document depressive symptoms and other adverse psychological consequences after firearm injury.  

► READ: Smith RN, Seamon MJ, Kumar V, Robinson A, Shults J, Reilly PM, Richmond TS. Lasting impression of violence: Retained bullets and depressive symptoms. Injury. 2018 Jan;49(1):135-140; and Jiang T, Webster JL, Robinson A, Kassam-Adams N, Richmond TS.  Emotional responses to unintentional and intentional traumatic injuries among urban black men: A qualitative study. Injury, published online Dec. 6, 2017.

Much debate has centered around the effectiveness of state and federal gun policies, which include background checks, bans on the sale of assault weapons and high-capacity magazines, Stand-Your-Ground laws, prohibitions associated with mental illness, lost or stolen firearm reporting requirements,   licensing and permitting requirements, firearm sales reporting and Recording Requirements, Child-Access Prevention Laws, Surrender of Firearms by Prohibited Possessors, minimum age requirements, concealed-carry laws, waiting periods, and gun-free zones. In a new report, RAND has synthesized the available scientific data on the effects of various firearm policies on firearm deaths, violent crime, the gun industry, participation in hunting and sport shooting, and other outcomes.

► READ: The Science of Gun Policy: A Critical Synthesis of Research Evidence on the Effects of Gun Policies in the United States. Santa Monica, CA: RAND Corporation, 2018. 

One problem in analyzing the effect of state gun laws is that firearms can easily be brought across state lines. In a new study, Elinore Kaufman, MD, MSHP, Douglas Wiebe, PhD, and colleagues found that states with stricter gun laws had lower rates of firearm-related homicide and suicide than states with more lenient policies. They also found similar effects in counties that bordered those states, indicating potential spillover across state lines.

► READ: Kaufman EJ, Morrison CN, Branas CC, Wiebe DJ. State Firearm Laws and Interstate Firearm Deaths From Homicide and Suicide in the United States. A Cross-sectional Analysis of Data by County. JAMA Intern Med. Published online March 5, 2018.

Most gun owners cite self-protection as a major reason for owning a gun. That instinct toward self-defense has given rise to “stand your ground” laws in a number of states, beginning with Florida in 2005.  These laws provide legal immunity to individuals using lethal force in self-defense. In the most comprehensive evaluation of Florida’s Stand Your Ground Law, Douglas Wiebe, PhD and colleagues found the law was associated with a significant increase in homicides and homicides by firearm, but no change in rates of suicide or suicide by firearm.

► READ:  Humphreys DK, Gasparrini A, Wiebe DJ. Evaluating the Impact of Florida’s “Stand Your Ground” Self-defense Law on Homicide and Suicide by Firearm: An Interrupted Time Series Study. JAMA Internal Medicine 2017;177(1):44–50. 

What other steps can be taken to reduce gun violence, given the ubiquity of guns in the United States? Researchers have tried to identify modifiable risk factors in the environment and in the interaction of individuals in the environment. A novel study asked young male gunshot assault victims to describe their minute-by-minute movements over the course of the day of the gunshot assault. A research team including Therese Richmond, CRNP, PhD and Douglas Wiebe, PhD identified “situational triggers” of gunshot assault in urban environments that could be targeted for intervention. In another study, John MacDonald, PhD, MA and colleagues found that at clearing and cleaning up vacant lots led to a 29 percent reduction in gun violence in the neighborhood.

► READ: Branas CC, South E, Kondo MC, Hohl BC, Bourgois P, Wiebe DJ, MacDonald JM. Citywide cluster randomized trial to restore blighted vacant land and its effects on violence, crime, and fear. Proceedings of the National Academy of Sciences, published online Feb. 26, 2018; and Dong B, Branas CC, Richmond TS, Morrison CN, Wiebe DJ. Youth’s Daily Activities and Situational Triggers of Gunshot Assault in Urban Environments. Journal of Adolescent Health, 2017 Dec;61(6):779-785.

Some look to popular culture, not to firearms themselves, to explain the levels of firearm violence in the United States. They cite exposure of youth to increasing levels of violence in movies, television, and video games as an important factor, although that link remains hotly debated.  Dan Romer, PhD and colleagues have recently documented increased levels of gun violence in PG-13 movies. As a result, they note, “movie-going families are now undergoing an experiment in which children of any age can enter a theater to watch a PG-13 film in which the protagonists gain power, settle conflicts, and kill or are killed by lethal weapons.”

► READ: Romer D, Jamieson PE, Jamieson KH. The Continuing Rise of Gun Violence in PG-13  Movies, 1985 to 2015. Pediatrics. 2017;139(2):e20162891.

We end this post by pointing to a 2007 Washington Post opinion piece by Dr. John Pryor, a surgeon who directed the trauma program at the Hospital of the University of Pennsylvania. In the piece, “The War in West Philadelphia” he likened urban gun violence to war, and recounts the human toll of firearm violence, the despair, the tragic loss of life, the devastated families. He stated,

More young men are killed each day on the streets of America than on the worst days of carnage and loss in Iraq. There is a war at home raging every day, filling our trauma centers with so many wounded children that it sometimes makes Baghdad seem like a quiet city in Iowa.

Dr. Pryor knew what he was talking about: he had served at a combat hospital in Abu Ghraib, Iraq in 2006. On his second tour of duty, as a member of the U.S. Army Surgical Unit in Iraq, Dr. Pryor was killed on December 25, 2008. Honoring his legacy of saving lives is a fitting place to begin this conversation.