diff --git a/CHANGES.rst b/CHANGES.rst
index 2065dfd..f4e178d 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -2,6 +2,17 @@ Changelog
 =========
 
 
+dev (not yet released)
+~~~~~~~~~~~~~~~~~~~~~~
+
+Bug fixes and minor changes
+---------------------------
+
++ `#171`_: Fix `dumpinvestigation.py` example script
+
+.. _#171: https://github.com/icatproject/python-icat/pull/171
+
+
 .. _changes-1_7_0:
 
 1.7.0 (2025-12-04)
diff --git a/doc/examples/dumpinvestigation.py b/doc/examples/dumpinvestigation.py
index 6dcbe57..209530f 100644
--- a/doc/examples/dumpinvestigation.py
+++ b/doc/examples/dumpinvestigation.py
@@ -29,7 +29,7 @@ def get_investigation_id(client, invid):
     if len(l) == 2:
         # one colon, invid == name:visitId
         query.addConditions({"visitId": "= '%s'" % l[1]})
-    else:
+    elif len(l) > 2:
         # too many colons
         raise RuntimeError("Invalid investigation identifier '%s'" % invid)
     return client.assertedSearch(query)[0]