diff --git a/consensus/types/src/state/committee_cache.rs b/consensus/types/src/state/committee_cache.rs
index 4a28f3c689..e76b0d2421 100644
--- a/consensus/types/src/state/committee_cache.rs
+++ b/consensus/types/src/state/committee_cache.rs
@@ -332,7 +332,7 @@ impl CommitteeCache {
         self.shuffling_positions
             .get(validator_index)?
             .0
-            .map(|p| p.get() - 1)
+            .map(|p| p.get().saturating_sub(1))
     }
 }