diff --git a/transactionoutbox-core/src/main/java/com/gruelbox/transactionoutbox/spi/Utils.java b/transactionoutbox-core/src/main/java/com/gruelbox/transactionoutbox/spi/Utils.java
index da52b267..1b7f51a3 100644
--- a/transactionoutbox-core/src/main/java/com/gruelbox/transactionoutbox/spi/Utils.java
+++ b/transactionoutbox-core/src/main/java/com/gruelbox/transactionoutbox/spi/Utils.java
@@ -25,7 +25,7 @@ public static boolean safelyRun(String gerund, ThrowingRunnable runnable) {
     }
   }
 
-  public static boolean indexViolation(Exception e) {
+  public static boolean indexViolation(Throwable e) {
     return (e instanceof SQLIntegrityConstraintViolationException)
         || (e.getClass().getName().equals("org.postgresql.util.PSQLException")
             && e.getMessage().contains("constraint"))