The lingering effects of the slave trade

We investigate the historical origins of mistrust within Africa. Combining contemporary household survey data with historic data on slave shipments, we show that individuals whose ancestors were heavily raided during the slave trade today exhibit less trust in neighbors, relatives, and their local government.

We confirm that the relationship is causal by using the historic distance from the coast of a respondent’s ancestors as an instrument for the intensity of the slave trade, while controlling for the individual’s current distance from the coast. We undertake a number of falsification tests, all of which suggest that the necessary exclusion restriction is satisfied.

Exploiting variation among individuals who live in locations different from their ancestors, we show that most of the impact of the slave trade works through factors that are internal to the individual, such as cultural norms, beliefs, and values.

That is Nathan Nunn and Leonard Wantchekon in a new NBER working paper (ungated version here). It is the kind of paper that makes me wistful to be a macro-development researcher.

The basic result–that levels of trust trust today decrease with the intensity of the historic slave trade–is convincing. The suggested channel, cultural norms, seems less so. More plausible (to me): the slave trade undermined the development of legal and political institutions, and some of those deleterious effects (and the attendant insecurities) persist to this day.

The authors argue otherwise, but we need to be very careful with Afrobarometer data. A useful exercise for a budding development researcher: take an Afrobarometer survey (or a DHS survey, or a LSMS survey…) and try it out in the field. Fear and data humility will descend upon you in a cascade.