Atheist Revolution has an interesting post about findings that point towards clergy being more dangerous sex offenders than the larger population. It's worth a read.
As Stop Baptist Predators recently reported, this evidence exists. Male clergy accused of sex crimes were found to be more dangerous in some important ways than matched non-clergy offenders (Langevin, Curnoe, & Bain, 2000). And religiosity was positively associated with the number of convictions for sex crimes and the number of victims among convicted male sex offenders (Eshuys & Smallbone, 2006). It was also inversely related to the age of the victims (i.e., more religious offenders tended to victimize younger children).
As vjack points out in his article, I am often asked if clergy sexual abuse is worse than abuse by others. I don't really have scientific or statistical proof to back my thinking, but I've always though it likely. Clergy are trusted members of society and are therefore granted special privileges, including less oversight and undeserved trust. Plus, parishioners are slow to believe anything that will cast doubt on their pastors as it is perceived as casting doubt on their church. I've seen too many examples of a church circling the wagons to prevent damage to their institution while children are pushed aside and clergy are shuffled. It is modus operandi for Baptist churches, and as we've seen, the Catholic church has institutionalized the practice.
Thanks for the link love vjack!