From the U.S. Department of Justice's pamphlet:
Child predators—sexual offenders who act on their sexual interest directed toward children—come from all economic and social backgrounds. Other terms used for these offenders
include “pedophile” and “preferential sex offender.” However,
these terms have specific clinical definitions. This guide uses the
term “child predator” because it is a nonclinical term that anyone
can testify to in court. Experience gained through hundreds of investigations and interviews shows that the behavior of child predators usually develops in four stages:
✹ Awareness. An individual first comes to realize that he has a
sexual interest in children. This interest may manifest itself in
several ways. Usually, the individual gathers as much information
as possible on the subject in an attempt to understand
his feelings. In this early stage, the Internet provides access
both to a variety of information sources—newspaper articles,
newscasts, groups such as the North American Man/Boy Love
Association (NAMBLA)—and to online chats with other individuals
who may have similar interests.
✹ Fantasy. The individual uses the research that he has collected
as a source for sexual fantasizing and stimulation. Eventually,
the fantasy becomes more fixated, with an emphasis on child
pornography. An individual using a computer will exchange email
with others who share the same interests and save these
messages and all other related material using some type of
computer storage medium.
✹ Stalking. Fantasy is no longer enough, and the individual
is now compelled to seek closeness to actual children. The
child predator will loiter at athletic events, parks, playgrounds,
school bus stops, and other locations where children are found
and may seek positions of trust in order to have access to children.
Hardcore child pornography plays an important role at
this stage. An individual using a computer will progress from
online chats with others with the same interests to chats with
potential victims. He may send them photos of himself in sexual
poses and request similar sexual photos in return.
✹ Molestation. The individual molests a child. The predator
using a computer sets up a meeting with the child he has
been corresponding with. Depending on the predator, the
meeting may lead either to a seduction or to abduction of the
. . .
However, be aware that an individual child predator may demonstrate all, some, or even none of these behaviors. Lack of evidence of the sequence of behaviors described above does not in itself clear a suspect.