diff --git a/samtools.wdl b/samtools.wdl
index bbd436740191eb3b4bb60390f76f31c6403a611e..aaa7ee3541029b3ca0b5d6351992a63659fff88c 100644
--- a/samtools.wdl
+++ b/samtools.wdl
@@ -1,8 +1,7 @@
 task Index {
     String? preCommand
     File bamFilePath
-
-    String bamIndexPath = bamFilePath + ".bai"
+    String bamIndexPath
 
     command {
         set -e -o pipefail