diff --git a/tools/BUILD b/tools/BUILD
index d668377..2b20874 100644
--- a/tools/BUILD
+++ b/tools/BUILD
@@ -78,6 +78,7 @@
         "-Xep:TypeParameterShadowing:ERROR",
         "-Xep:TypeParameterUnusedInFormals:WARN",
         "-Xep:URLEqualsHashCode:ERROR",
+        "-Xep:UnusedException:ERROR",
         "-Xep:UnsynchronizedOverridesSynchronized:ERROR",
         "-Xep:WaitNotInLoop:ERROR",
     ],