"There are, after all, many similarities between a legitimate business and a fencing business - the incomes of both depend on the scope of operations and the operator's skill at marketing; both need people who can be trusted, people who can remain loyal, people who can keep secrets or at least are discreet about what they say, people who are on time, and people who are dependable."[pgs. 2-3].
By associating himself with both worlds, Sam was playing a role in both worlds, and could have presumably lost touch with wrong and right. However, another important concept to consider in these legitimate/illegitimate business worlds, is the means to support them, and an opportunity to commit these acts.
Clearly, one must have the opportunity to commit deviant and legitimate acts if they are going to commit them at all. When committing a deviant act and the benefits outweigh the likelihood of being caught, then a crime will most likely be committed especially if the deviant in question has been exposed to a lot of criminal activity. Relying on Cloward and Ohlin's Opportunity Theory, one can make a reasonable guess as to whether a prospective criminal will in fact commit a crime. Take Vincent Swaggi, another fence mentioned in The Fence. Vincent, who had been exposed to a lot of criminal activity, clearly had the opportunity to commit more criminal acts once he had established himself as a fence. He had the means to do so, thereby meeting the criteria to act as a fence as described in the book as " a person [who] must be energetic, ingenious, capable of making sound decisions, quite personable. A modest amount of money, the opportunity to buy stolen property, and the willingness to do so are the necessary conditions."[pg. 8] So, clearly these conditions must be present to have the opportunity to commit a deviant act. Once established, like Vincent and Sam, there is also the opportunity for growth of a criminal business.