A new study in JAMA Pediatrics asserts that states with “permissive” gun control laws experienced higher pediatric firearm mortality rates following the 2010 Supreme Court decision in McDonald v. Chicago. The study analyzed data from 49 states spanning 1999 to 2023.
Unlike typical research, which compares crime or suicide rates before and after states change their laws and contrasts those changes with states that didn’t alter their laws, this study ignores how laws change over time. It categorizes the level of gun control laws in each state into one of three broad categories and assumes that is constant over time. It overlooks factors like law enforcement practices—such as arrest and conviction rates, imprisonment rates, or the death penalty—that influence crime.
The study labels states as “most permissive” or “permissive” and see if there is a rise in “excess” juvenile firearm deaths (homicides, suicides, and accidental deaths) after the 2010 McDonald v. Chicago ruling.
To determine expected deaths, Poissonregression was used to fit the data in prepolicy period (1999-2010), adjusting for time trends and legal status groupings. After model fitting, expected deaths were predicted for each year of the post policy period and for the total period (2011-2023).
— The paper assumes that all state laws remain unchanged. For example, a state like Colorado is listed as having permissive gun laws even though its laws got much stricter by the end of the period examined.
— It is hardly obvious how looking at the pattern of firearm homicides or firearm suicides over the years from 1999 to 2010 predicts how those types of firearm deaths could change after that date. Other factors such as arrest and conviction rates or income and poverty or unemployment or anything else could be quite different in the later period, but this study doesn’t account for any factors that could explain how crime or suicides or accidental deaths could change in the later 2011 to 2023 period.
— The categorizing states into three different groups (most permissive, permissive, and strict) is arbitrary. All sorts of different gun control laws are lumped together and how they are weighted and where the cut off points to determine what group a state is put into is arbitrary. Why not put the states on a zero to 100 scale? Why not account for different gun control laws separately as some may matter and others might not?
— Why look at homicides (which include murders and justifiable homicides) instead of just murders?
— Why look at firearm homicides instead of total homicides?
This JAMA study has gotten a lot of uncritical news coverage. Here is how the New York Times described the research.
Firearm deaths of children and teenagers rose significantly in states that enacted more permissive gun laws after the Supreme Court in 2010 limited local governments’ ability to restrict gun ownership, a new study has found.
In states that maintained stricter laws, firearm deaths were stable after the ruling, the researchers reported, and in some, they even declined. . . .
“It’s surprising how few of these are accidents,” Dr. Faust said. “I always thought that a lot of pediatric mortality from guns is that somebody got into the wrong place, and I still think safe storage is important, but it’s mostly homicides and suicides.” . . .
The study, published Monday in JAMA Pediatrics, examined the 13-year period after the June 2010 Supreme Court ruling that the Second Amendment, which protects an individual’s right to bear arms, applies to state and local gun-control laws. The decision effectively limited the ability of state and local governments to regulate firearms.
The researchers classified states into three categories based on their gun laws: most permissive, permissive and strict. They used a Centers for Disease Control and Prevention database to analyze firearm mortality trends from 1999 to 2010 — before the Supreme Court ruling — and compared them with the 13-year period afterward. . . .
