diff --git a/sc2ts/info.py b/sc2ts/info.py
index 50cefa1..a536192 100644
--- a/sc2ts/info.py
+++ b/sc2ts/info.py
@@ -1751,10 +1751,10 @@ def draw_subtree(
                     shown_nodes.append(u)
                 prev = u
 
+        multiple_mutations = []
+        reverted_mutations = []
         if mutation_labels is None:
             mutation_labels = collections.defaultdict(list)
-            multiple_mutations = []
-            reverted_mutations = []
             use_mutations = np.where(np.isin(ts.mutations_node, shown_nodes))[0]
             sites = ts.mutations_site[use_mutations]
             for mut_id in use_mutations: