diff --git a/spiffworkflow-backend/src/spiffworkflow_backend/routes/process_api_blueprint.py b/spiffworkflow-backend/src/spiffworkflow_backend/routes/process_api_blueprint.py
index 427a08e06..37a1b8280 100644
--- a/spiffworkflow-backend/src/spiffworkflow_backend/routes/process_api_blueprint.py
+++ b/spiffworkflow-backend/src/spiffworkflow_backend/routes/process_api_blueprint.py
@@ -1295,7 +1295,7 @@ def process_instance_task_list(
             )
             .first()
         )
-        if step_detail is not None:
+        if step_detail is not None and process_instance.bpmn_json is not None:
             bpmn_json = json.loads(process_instance.bpmn_json)
             bpmn_json["tasks"] = step_detail.task_json
             process_instance.bpmn_json = json.dumps(bpmn_json)