diff --git a/doc/src/connection.rst b/doc/src/connection.rst
index 22f1f066..eac2f001 100644
--- a/doc/src/connection.rst
+++ b/doc/src/connection.rst
@@ -613,6 +613,8 @@ The ``connection`` class
         `psycopg2.extensions`: see :ref:`connection-status-constants`
         for the available values.
 
+        The status is undefined for `closed` connectons.
+
 
     .. method:: lobject([oid [, mode [, new_oid [, new_file [, lobject_factory]]]]])