Although it might seem that such "tough-on-crime" legislation would increase public safety, the opposite has been found to be true. Felons who calculate they will receive the same punishment for murder as they would for having a third strike, kill their victims to avoid detection and police officers to avoid apprehension.
Many police organizations oppose "three-strikes" laws for this reason, said senior author John Sloan III, an associate professor of Justice Studies at the Birmingham campus.
The article "Unintended Consequences of Politically Popular Sentencing Policy: The Homicide-Promoting Effects of 'Three Strikes' in U.S. Cities (1980-1999)," written with assistant professors Tomislav V. Kovandzic and Lynee M. Vieraitis, appears in the current issue of Criminology & Public Policy.
In the late 1980s and early 1990s, policy makers facing intense public pressure to "do something" about the high rate of violent crime, responded by strengthening laws targeting repeat offenders. Between 1993 and 1996, 25 states and the federal government enacted laws known by the baseball metaphor "three strikes and you're out." These laws generally reduce the discretion of judges by mandating severe prison sentences for third felony convictions.
The authors warn that though this intuitively might seem like effective policy, intuition alone isn't a sound basis for judging what will or won't work, at what cost, and with what side effects.
The Alabama criminologists replicated the results of "The Lethal Effects of Three-Strikes Laws," by Thomas B. Marvell and Carlisle E. Moody, which appeared in the January 2001, issue of the Journal of Legal Studies.
"According to Marvell and Moody ... criminals facing lengthy prison terms upon conviction for a third strike may take steps to reduce the chances of being caught, prosecuted, and convicted by changing their modus operandi," Sloan and his colleagues wrote. "That is, during the commission of an ordinarily non-lethal offense, an offender may decide to kill victims, witnesses or police officers to reduce the chance of apprehension."
Marvell and Moody looked at data by state.
"They found that states with three-strikes laws had significantly higher rates of homicide than states that did not during a roughly comparable period," Sloan told United Press International.
Sloan and his colleagues looked at data by city. They divided the 188 largest U.S. cities, those with populations of 100,000 or more, into two groups -- those in states with three-strikes laws and those in states without such laws.
The researchers then collected data on homicide from the FBI's Uniform Crime Reports from 1980 to 1999. These data were collected from time periods both before and after the laws were passed.
"That's to control for any possible trends than might have begun prior to the passage of the laws that could have affected the crime rates afterward," Sloan said.
The criminologists also controlled for seven socio-demographic variables that previous research has shown to be important correlates of homicide: percent of people who are African-American, percent of the population aged 18 to 24, percent of female-headed households, percent of the population living below the poverty line, income inequality, percent of the population living alone, and prison population (a negative correlate).
Additionally, the researchers controlled for a number of crime variables.
"If, for example, robbery was going up, that could cause homicide to go up," Sloan said.
The results obtained by the Alabama criminologists were almost identical to those of Marvell and Moody. During the year in which a three-strikes law was passed (which the authors define as the "short term"), homicide rates increased, on average, by 13 percent to 14 percent. The cumulative effect from 1980 to 1999 (the "long term") was an increase in homicide rates in cities in the three-strikes states from 16 percent to 24 percent.
"These laws not only don't work, they increase homicides," Sloan told UPI.
Sloan said most crime control policy arises from knee-jerk reactions to particularly heinous offenses that, by definition, are not the norm. But because these crimes generate so much attention, pressure is brought to bear on legislators to "do something."
It's politically expedient to impose severe measures rather than looking at other kinds of solutions, the professor said, and too often the costs and unintended consequences of "get-tough" laws are not considered.