Indeed, the literature is conflicted. Some academics, like Harvard Medical School’s Howard Schaffer, say that the number of gambling addicts has not increased alongside casino expansion. Douglas Walker, a professor of economics at the College of Charleston, has criticized Grinol’s methodology in studying casino-related crime.

http://www.salon.com/2012/03/09/casino_capitalism_as_gambling_spreads_metaphor_becomes_reality/singleton/