Expanding DNA databases, rather than longer prison sentences, could deter people from committing crimes, writes Stanford University's Keith Humphreys in an op-ed at the Washington Post.
A recent working paper from researchers in the US and Denmark found that DNA profiling in Denmark increased the likelihood that someone would get caught and reduced the rate that someone would re-offend. University of Virginia economist Jennifer Doleac and her colleagues took advantage of a natural experiment in Denmark when police there increased their DNA collection from 4 percent to 40 percent of people who were arrested and charged for the equivalent of a US felony.
In their cohort of 38,000 Danish men, the researchers found that being added to the database decreased the rate of recidivism by 43 percent. They also estimated that for every 1 percent increase in the probability of being caught, crime went down by about 2 percent. "Our results thereby show that policies that increase the identification of criminal offenders are an effective tool to reduce crime and increase public safety," Doleac and her colleagues write.
Humphreys adds that "harsher criminal sentences favored by self-styled 'tough on crime' politicians" have not been shown to similarly reduce crime rates.