diff --git a/CHANGELOG.md b/CHANGELOG.md
index c4d0092..20bc107 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
+### Fixed
+
+- Avoid deprecation warning from the ijson package.  https://github.com/OpenDataServices/flatten-tool/pull/458
+
 ## [0.26.0] - 2024-08-22
 
 ### Fixed
diff --git a/flattentool/json_input.py b/flattentool/json_input.py
index bba3a5e..3a4309a 100644
--- a/flattentool/json_input.py
+++ b/flattentool/json_input.py
@@ -47,6 +47,10 @@ class BadlyFormedJSONError(FlattenToolError, ValueError):
 
 
 class BadlyFormedJSONErrorUTF8(BadlyFormedJSONError):
+    """
+    Deprecated. This exception is no longer raised.
+    """
+
     pass
 
 
@@ -302,7 +306,7 @@ def __init__(
             else:
                 path = root_list_path.replace("/", ".") + ".item"
 
-            json_file = codecs.open(json_filename, encoding="utf-8")
+            json_file = codecs.open(json_filename, "rb")
 
             self.root_json_list = ijson.items(json_file, path, map_type=OrderedDict)
 
@@ -310,8 +314,6 @@ def __init__(
             self.parse()
         except ijson.common.IncompleteJSONError as err:
             raise BadlyFormedJSONError(*err.args)
-        except UnicodeDecodeError as err:
-            raise BadlyFormedJSONErrorUTF8(*err.args)
         finally:
             if json_filename:
                 json_file.close()
diff --git a/flattentool/tests/test_json_input.py b/flattentool/tests/test_json_input.py
index b15b3da..acfbf15 100644
--- a/flattentool/tests/test_json_input.py
+++ b/flattentool/tests/test_json_input.py
@@ -8,11 +8,7 @@
 
 import pytest
 
-from flattentool.json_input import (
-    BadlyFormedJSONError,
-    BadlyFormedJSONErrorUTF8,
-    JSONParser,
-)
+from flattentool.json_input import BadlyFormedJSONError, JSONParser
 from flattentool.schema import SchemaParser
 from flattentool.tests.test_schema_parser import object_in_array_example_properties
 
@@ -35,9 +31,6 @@ def test_jsonparser_bad_json_utf8():
     name = os.path.join(
         os.path.dirname(os.path.realpath(__file__)), "fixtures", "bad-utf8.json"
     )
-    # matches against the special error type
-    with pytest.raises(BadlyFormedJSONErrorUTF8):
-        JSONParser(json_filename=name)
     # matches against our base error type
     with pytest.raises(BadlyFormedJSONError):
         JSONParser(json_filename=name)