Do Higher Salaries Lower Petty Corruption? a Policy Experiment on West Africa’s Highways1

In one of the most ambitious public sector reform experiments in Africa, the Ghana government doubled its police officer salaries in 2010 in part to mitigate petty corruption on its roads. Neighboring countries in the West African region left their police salaries unchanged. Using unique data on bribes paid from over 2,100 truck trips in West Africa and representing over 45,000 bribe opportunities, we evaluate the reform impacts on petty corruption using a difference-in-difference method that exploits the exogenous policy experiment. By following bribes paid by the same trucks in different countries as well as to different civil servants in Ghanaian bribe taking we can identify whether salaries affect both the number of bribes and the amount given by truckers. Rather than decrease petty corruption, the salary policy significantly increased the police efforts to collect bribes, the value of bribes and the amounts given by truck drivers to policemen in total. Robustness checks show the higher bribe amount is robust to alternative specifications. Moreover, we do not find that Ghana policemen collected significantly fewer bribes than other officials in the same country. (JEL K42, R40) 1 We are very grateful to the West African Trade Hub and USAID for providing access to the data. Funding was graciously provided by an International Growth Center grant. We also thank without implicating Daniel Bromley, and participants at University of Wisconsin, Oxford University and the University of California, Berkeley for comments and Srini Vasudevan for data cleaning. The usual disclaimer applies.