diff --git a/authzgroups.php b/authzgroups.php
index 3a2c574..68a535c 100644
--- a/authzgroups.php
+++ b/authzgroups.php
@@ -139,7 +139,8 @@ class authzgroups
                            500);
     if ($object === "/") $object = "";
     $rc = $this->allow ($module, $user, "/$object");
-    trigger_error ("authzgroups : accessRight ('$module','$user','/$object')".
+    if ($this->debug)
+      trigger_error ("authzgroups : accessRight ('$module','$user','/$object')".
                    "=$rc", E_USER_NOTICE);
     if ($rc !== "NO")
       return TRUE;
@@ -167,7 +168,8 @@ class authzgroups
                            500);
     if ($object === "/") $object = "";
     $rc = $this->allow ($module, $user, "/$object");
-    trigger_error ("authzgroups : accessWrite ('$module','$user','/$object')".
+    if ($this->debug)
+      trigger_error ("authzgroups : accessWrite ('$module','$user','/$object')".
                    "=$rc", E_USER_NOTICE);
     if ($rc === "RW")
       return TRUE;
@@ -196,8 +198,9 @@ class authzgroups
                            500);
     if ($object === "/") $object = "";
     $rc = $this->allow ($module, $user, "/$object");
-    trigger_error ("authzgroups : accessReadOnly ('$module','$user','/$object')"
-                   ."=$rc", E_USER_NOTICE);
+    if ($this->debug)
+      trigger_error ("authzgroups : accessReadOnly ('$module','$user',".
+                   "'/$object')" ."=$rc", E_USER_NOTICE);
     if ($rc === "RO")
       return TRUE;
     if ($user === "anonymous")