diff --git a/beacon-chain/core/state/state_transition.go b/beacon-chain/core/state/state_transition.go
index bbd59dc4d4..e9ab5a22ec 100644
--- a/beacon-chain/core/state/state_transition.go
+++ b/beacon-chain/core/state/state_transition.go
@@ -120,6 +120,10 @@ func crossLinkCalculations(
 			st.LastStateRecalculationSlot(),
 			attestation.GetSlot(),
 		)
+		if err != nil {
+			return nil, err
+		}
+
 		indices, err := v.AttesterIndices(shardCommittees, attestation)
 		if err != nil {
 			return nil, err