@quagzlor
You'd be surprised how many stories of beaten children reflect that teachers and government officials are indeed like this. “Oh, he looks like a nice, friendly guy, that means he can't be beating his child in private.” vs “Oh, he looks ugly and scary — then we need to be careful.”
I read a story once from two children who were essentially held for 7 years by a step-parent with their biological parent powerless to stop it; they were beaten at times to the point of the neighbours calling the police, who would come over, and he would be friendly and kind with them and just calmly explain that something simply fell over and that he understands their concern but that it's all fine and then the police would go away without further checking and he would resume his beating.
Conmen work like this every day; they appear as actual friendly people whom one thinks one can trust, not like Harvey Mudd in fiction.