diff --git a/src/tgbaalgos/hoa.cc b/src/tgbaalgos/hoa.cc
index f1322af4c..4c68ac006 100644
--- a/src/tgbaalgos/hoa.cc
+++ b/src/tgbaalgos/hoa.cc
@@ -131,6 +131,11 @@ namespace spot
 	is_deterministic = deterministic;
 	is_complete = complete;
 	has_state_acc = state_acc;
+
+	// If the automaton declares that it is deterministic or
+	// state-based, make sure that it really is.
+	assert(!aut->is_deterministic() || deterministic);
+	assert(!aut->has_state_based_acc() || state_acc);
       }
 
       void number_all_ap()