Reread this 2011 article from the University of Chicago questioning the effectiveness of current sex offender laws. Two studies are cited that conclude that these laws do not support the intended results.
Two studies in the latest issue of The Journal of Law and Economics cast doubt on whether sex offender registry and notification laws actually work as intended.
One study, by J.J. Prescott of the University of Michigan and Jonah Rockoff of Columbia University, found that requiring sex offenders to register with police may significantly reduce the chances that they will re-offend. However the research also finds that making that same registry information available to the broader public may backfire, leading to higher overall rates of sex crime.
Meanwhile, another study by University of Chicago Ph.D. student Amanda Agan finds no evidence that sex offender registries are at all effective in increasing public safety.
The first study, Prescott and Rockoff—Do Sex Offender Registries and Notification Laws Deter Crime? concludes that:
Taken as a whole, the research shows that while police registration discourages sex offender recidivism, public notification actually encourages it.
The second study, Amanda Agan—Sex Offender Registries: Fear Without Function? concludes:
Agan finds no evidence that sex offender registries are effective in increasing public safety.