+$group_id = (int)$request->getParameter('group_id');
+if ($group_id && !$user->isGroupValid($group_id)) {
+ header('Location: access_denied.php');
+ exit();
+}
+// End of access checks.
+
+if ($group_id) {
+ // We are passed a valid group_id (most likely from group_edit.php).
+ // Set on behalf group accordingly.
+ $user->setOnBehalfGroup($group_id);
+}