He makes claims that he provides no evidence for. I have given an example as you requested. I don't see what there is to ask.
Responsible social scientists will acknowledge the limits of their data and stay within them. Bergman on the other hand, not content with the fact that we don't have figures on the Witness crime rate, murder rate, physical abuse and so on decides that the lack of actual evidence should be no bar to him pontificating on those subjects. No doubt Bergman has a lot of experience with Witnesses who had various difficulties, but no amount of experience entitles an academic (if he wishes his work to be accepted as such, which apparently he does) to make such sweeping generalizations without evidence.
Singelenberg made this appropriate comment in reviewing Bergman's bibliography:
So far, any significant association between upbringing in this religious milieu and criminal activities has not been demonstrated. The same goes for a JW lawyer who swindled his fellow believers (p. 241). These are unfortunate events, but by emphasizing these and similar isolated incidents it is unclear what information the writer wants to convey to the reader other than the negative stigmatization of a religious minority.
It is funny that you say Bergman has the guts to sign his name to his work because, as I noted earlier, he has used a number of false names in the past - then he has reviewed his own work positively without mentioning that is was his work!
And by the way I have not written any work on the Witnesses with academic pretensions. If I do you and Bergman are welcome to evaluate it. It is you making the cheap shots here.
Slim