Militia co-optation and communal violence displacement in the Sahel: a difference-in-differences evaluation of security outcomes and civilian protection accountability under decentralized armed-group pacts

Decentralized armed-group pacts in the Sahel have been promoted as a means of co-opting militias into state security architectures, yet their effects on communal violence displacement and civilian protection accountability remain poorly understood. Using a before-after-control-impact design with between-cluster standard deviation of 6.0, residual standard deviation of 4.5, and intraclass correlation of 0.64, power was estimated across 2000 design cells for cluster counts of 8, 16, 24, and 32 and effect sizes of 3, 5, and 8 percentage points. The analysis indicates that 56 clusters are required to detect a 5 percentage point effect at 80% power. Minimum detectable effects decline as cluster counts increase, and the receiver operating characteristic demonstrates acceptable discrimination. The framework clarifies the conditions under which decentralized pacts can be evaluated credibly and identifies the accountability mechanisms that must accompany co-optation for civilian protection to be sustained.