diff --git a/bcipy/task/paradigm/rsvp/copy_phrase.py b/bcipy/task/paradigm/rsvp/copy_phrase.py
index 1c385f0f..a7f335db 100644
--- a/bcipy/task/paradigm/rsvp/copy_phrase.py
+++ b/bcipy/task/paradigm/rsvp/copy_phrase.py
@@ -686,6 +686,7 @@ def compute_button_press_evidence(
         """
         if (not self.should_compute_button_press_evidence()):
             return None
+        assert self.current_inquiry, "Current inquiry is required"
         probs = compute_probs_after_preview(
             self.current_inquiry.stimuli[0],
             self.alp,
@@ -696,8 +697,8 @@ def compute_button_press_evidence(
 
     def should_compute_button_press_evidence(self) -> bool:
         """Determine if button press evidence should be computed"""
-        return self.parameters["show_preview_inquiry"] and self.parameters[
-            'preview_inquiry_progress_method'] > 0 and self.current_inquiry
+        return bool(self.parameters["show_preview_inquiry"] and self.parameters[
+            'preview_inquiry_progress_method'] > 0 and self.current_inquiry)
 
     def compute_device_evidence(
             self,