According a story on the Fox News site, Douglas Perlitz was a missary working in Haiti for Project Pierre Toussaint. This was funded by Fairfield University - a Catholic institution. He was recently indicted on sex abuse charges. It is alleged that he used his position to lure children into his homes and had sex with them. The mission work was just a cover.
The question must be asked, what went wrong? Surely, this was funded with the best of intentions. Surely, this has horrified almost all of those involved with this project. I can't say, since I don't know all the details. But one thing seems to be clear to me. It appears that Perlitz was working alone for the most part. In the book of Acts, missionaries usually went out in pairs or even larger groups. Most protestant missionaries to the developing world are husband and wife teams. In many of these cultures one is not considered an adult until one has a wife and children. So one simple safe guard would be to have people working in teams of two or more. It's not fool proof. But if one person sees something is amis, they can intervene. It would greatly reduce the chance of this happening in the future.