When the notorious American bank robber Willy Sutton was asked why he robbed banks he famously said: 'Because that's where the money is.'
Likewise, criminal psychologists agree that paedophiles - sexual deviants who prey on children - will purposely find employment where children are: at schools, playgrounds, day-care centres and amusement parks.
Although police psychologists say that paedophiles can never be cured, after convicted sex offenders have served their sentences they are released back into the community. Each year in the US alone, more than 60,000 arrests are made for sex crimes against children. In many cases the same paedophiles are arrested repeatedly.
Public outcry over paedophiles surged the US after the 1994 rape and murder of seven-year-old Megan Kanka by a convicted sex offender who lived across the street from her home. In the years that followed Megan's killing, various US states began to enact regulations requiring law enforcement authorities to identify convicted sex offenders to the public, either through the media, or the internet. These directives have been informally called Megan's Law.
While more than 550,000 sex offenders have been registered, it is believed that as many as a 100,000 paedophiles are missing or have no known current address.