diff --git a/contracts/src/arbitration/KlerosCore.sol b/contracts/src/arbitration/KlerosCore.sol
index 472f28614..cfee3e003 100644
--- a/contracts/src/arbitration/KlerosCore.sol
+++ b/contracts/src/arbitration/KlerosCore.sol
@@ -222,7 +222,7 @@ contract KlerosCore is IArbitratorV2, UUPSProxiable, Initializable {
         uint256[4] memory _timesPerPeriod,
         bytes memory _sortitionExtraData,
         ISortitionModule _sortitionModuleAddress
-    ) external initializer {
+    ) external reinitializer(1) {
         governor = _governor;
         pinakion = _pinakion;
         jurorProsecutionModule = _jurorProsecutionModule;