diff --git a/gitosis/run_hook.py b/gitosis/run_hook.py
index 02fc055..1c66252 100644
--- a/gitosis/run_hook.py
+++ b/gitosis/run_hook.py
@@ -66,10 +66,12 @@ class Main(app.App):
         os.umask(0022)
 
         git_dir = os.environ.get('GIT_DIR')
-        log.debug("GIT_DIR", git_dir)
         if git_dir is None:
             log.error('Must have GIT_DIR set in enviroment')
             sys.exit(1)
+        else:
+            log.debug("GIT_DIR", git_dir)
+
 
         if hook == 'post-update':
             log.info('Running hook %s', hook)