You can find paedophiles in every group of adults that regularly interact with children in a position of authority. Teachers, doctors, clergy, scout leaders, police, sports coaches. There are no exceptions.
One of the reasons the Catholic Church is taking such a publicity beating is that for the last 60 years it has been the policy of the Catholic Church to not publicly censure or punish those priest involved in inappropriate relations with children.
In fact, church hierarchy has paid off and discredited witnesses, covered up evidence, and impeded police investigations.
No other group to my knowledge has made such a long-term and concerted effort to cover up its criminal activities in relation to children.