What’s the biggest misconception about the causes of murder?
Liberals believe economic deprivation leads to violence and higher murder rates. Conservatives blame lack of deterrence. Neither theory fits the evidence.
What does your research show?
Looking back in history, I found that low murder rates are most likely to occur when Americans have a strong level of trust in the government and in each other.
What data led you to this conclusion?
I found a strong correlation from the 1640s to the 1920s between low murder rates and an increase in the percentage of new counties in any decade that are named for national heroes. It’s kind of an unconscious way to say we believe in our country, we believe in our national leaders, we believe in each other.
What other evidence did you uncover?
During the American Revolution people in the Shenandoah Valley sent more material support and manpower to the Continental Army than anyone else in the country. So I expected the homicide rate there would be stable or even drop. And that’s what I found had happened. By contrast, there was all-out civil war in parts of the Deep South, like South Carolina, Georgia and the backcounty. Homicide rates spiked there and stayed high for a generation.
Would there be fewer murders now if Americans were more patriotic?
Yes, if you mean by patriotism genuine love of country and fellow Americans, the sense that we are all one people. But most patriotism in the United States since the mid-19th century has been “I’m an American and you’re not,” and that kind of patriotism is destructive. It draws the line between us and them within the society rather than between us and people who live outside our society. As long as that kind of patriotism is out there, it’s the problem, not the solution.
During what period of history have we had the highest murder rates?
Things began to go out of control before the start of the Civil War, when the effort to build a strong nation failed and the twoparty structure broke down. People didn’t feel a connection to Americans on the other side of these great political divides. And our homicide rates are still higher than those in other affluent nations.
How big a factor has race been?
Homicide rates were low for both whites and blacks during the pre-Revolutionary era because there was tremendous political stability. There was a deep-seated sense of hierarchy that included not just slaves, but apprentices and indentured servants. These were violent labor systems but not as violent as after the Revolution when the idea that we’re all equals was thrown into the mix.
How did things change after slavery was abolished?
Before the 20th century, African Americans did not have the highest homicide rates. White European Americans were the most violent and lethal. But those data curves crossed in the 1890s, and since that time African Americans have been disproportionately more likely to commit murder and be murdered.
How has the proliferation of guns affected murder rates?
We would be a relatively homicidal society today even if we were using baseball bats and dinner knives. But guns have made a difference ever since firearms that are loaded all the time and repeat became available.
What patterns do you see in rates of murders of spouses or lovers?
Until the early 1800s, marital and romance homicides were extremely rare. Suddenly in the 1830s and 1840s, they become much more common in the North, where there were more opportunities for work and education of women. The view of marriage shifted from the husband’s authority to a balance between husband and wife. And that prompted a rise in the number of men who killed their wives or lovers.
Is this happening today with the increase in working women?
It’s possible that the progress toward gender equality caused a short-term increase in domestic murders of women in the late 1960s and 1970s. But we do not have reliable counts of the number of domestic homicides that occurred.
Does how we are governed affect why people kill each other?
Polling data since the late 1930s reveal that to be the case. Murder rates are lower when there is a higher percentage of people who say they trust the government to do the right thing most of the time.
Is there less murder when the U.S. unites against a common enemy?
The love of country has to be very widespread and deeply felt for that to occur. Homicide rates didn’t go down after 9/11 because the attack on the World Trade Center didn’t change how we feel about our fellow Americans. World War II demanded tremendous sacrifice: People were fighting and dying. When we’ve mobilized against a deadly enemy—a clear and present danger like Japan, Germany or Italy—people trusted the government to do the right thing. People have not had the same level of trust in the fight against terrorism.
Can strong political leadership lower the murder rate?
The potential is there if political leaders really band together and elites emphasize what we have in common instead of what divides us. But no one was more eloquent about what we have in common as Americans than Abraham Lincoln, and he tried in his own way to come up with centrist solutions to everything. He was the greatest leader in our history and he ended up a murder statistic.
Is the murder rate linked to the popularity of presidents?
Only insofar as the popularity of a president is linked with general trust in government. Even as Franklin Roosevelt’s popularity decreased in the late 1930s, before World War II, the homicide rate went down and trust in government kept going up because poor and middle class people deeply believed in the New Deal.
What about other presidents?
The homicide rate among whites spiked in 1980, at the end of Jimmy Carter’s administration. There was tremendous anger over welfare, affirmative action, the hostage crisis in Iran. It wasn’t just anger at Jimmy Carter. Trust in government had declined since the Vietnam era. With the sweeping victory for Ronald Reagan, the homicide rate dropped among whites as fast each year as it dropped during FDR’s first six years in office.
Trust in government among whites jumped back up. It wasn’t just Ronald Reagan. There was a sense among conservative whites that there was a return to traditional values after all the turmoil that began in the 1960s and that the silent majority had been empowered. Trust in government is a complex phenomenon. It’s deeper than how we feel about a particular president.
What trend do you see now?
When Barack Obama was elected, I predicted the homicide rate would drop dramatically in urban America, particularly among minorities and African Americans—not because of Obama per se but because having an African-American president would give people a sudden surge of faith in the system. Since last year, homicide rates in Baltimore, New Orleans and Dallas were flat, and down 11 to 67 percent in other cities. Sexual assaults and armed robberies dropped after the election.
Do you think murder rates will drop elsewhere in the country?
I don’t know. How disempowered are conservatives feeling? That’s a big question right now.
Originally published in the April 2010 issue of American History. To subscribe, click here.