diff --git a/tests/test_prison_alignment_evidence.py b/tests/test_prison_alignment_evidence.py
index 9d67aa7..f106f3f 100644
--- a/tests/test_prison_alignment_evidence.py
+++ b/tests/test_prison_alignment_evidence.py
@@ -13,7 +13,13 @@ from test_prison_alignment_proof import Scene as AlignmentScene
 
 
 def build():
-    route_scene=ApproachScene();route=route_scene.run()
+    route_scene=ApproachScene()
+    # A complete synthetic chain needs both reachable pulse distances and
+    # receipt-valid mouse dispatch. Keep the two ownership checks below0.5s;
+    # this different physical model is not a native motion claim.
+    route_scene.guard_cost=.18
+    route_scene.acceleration=12.;route_scene.braking=12.
+    route=route_scene.run()
     scene=AlignmentScene()
     scene.now=route_scene.now;scene.next_sample=route_scene.next_sample
     scene.geometry=copy.deepcopy(route_scene.geometry)