diff --git a/jwst/stpipe/core.py b/jwst/stpipe/core.py
index 0c3df08d71..35286471df 100644
--- a/jwst/stpipe/core.py
+++ b/jwst/stpipe/core.py
@@ -105,6 +105,7 @@ def run(self, *args, **kwargs):
 
     @wraps(Step.__call__)
     def __call__(self, *args, **kwargs):
+        raise Exception()
         if not self.parent:
             warnings.warn(
                 "Step.__call__ is deprecated. It is equivalent to Step.run "