Whenever my landlord introduced me to one of his 'good friends', I knew that he was almost certainly a crook, probably from another ethnic group, a member of a criminal fraternity stretching back decades with a common background of gambling dens, police raids, gaols, diamond smuggling, drug rings, and all the rest. These were the men he turned to when he needed to trust someone, not his family or his fellow tribesmen.

Diego Gambetta, Trust - Making and Breaking…, loc. 2392