To deter criminals, expand DNA databases instead of prisons

Because DNA evidence is found at many crime scenes (e.g., most rapes and other violent assaults), DNA databases raise the odds that the offender will be identified and convicted. As has been shown in many other criminal justice programs (e.g., “swift, certain, and fair” supervision programs discussed in Wonkblog here and here), raising the likelihood of being punished deters repeat offending far more than does increasing the severity of criminal penalties.