Deaf children are at a great risk of abuse, there was an article about it in the newspaper not long ago over here.
Since they're deaf they don't speak (in words that is) and so, to the predatory people, they look like a a victim that can't testify about what they have done to them. Easy pray.
For that reason alone, I don't feel surprised to read that piece of news. Disgusted yes, but not surprised.
After all, the predatory person seeks a job/position where there is ample pray. And who has greater access to the weak and helpless than a man of the cloth?