Scamming and the reputation of drug dealers on Darknet Markets.

Summary In this paper I investigate the role of e-reputation mechanisms on illegal platforms that specialize in drug sales. I ask whether online reputation systems can limit the risk of scamming (i.e. fraud) by dishonest sellers, and thus prevent Akerlof-like market destruction. I do so by analyzing all published offers on the second-largest platform operating on March 18th 2017 (Hansa). Three types of drugs show relatively low scamming risks, with the average probability that a random seller effectively send the ordered good of over 83%. The recent shutdowns of the two leading platforms are likely to increase this probability by 2.7 to 9.7%. Endogeneity may either lead us to overestimate the effect of e-reputation mechanisms (e.g., unobserved heterogeneity in sellers) or underestimate it (e.g., better-functioning markets may attract more scammers).