Yea, I think what some people are worried about though, are the (a) possibility of many false positives and (b) the collateral damage with "common crimes". In the latter I mean: how far into the realm of everyday rule-breaking will these agencies go? Will you get a ticket mailed to you because you rolled through a stop sign and your license plate was captured? Will you get police officer (with warrant) at your door to search your premises because you purchased a book about marijuana growing?