diff --git a/acme/adders/reverb/structured.py b/acme/adders/reverb/structured.py
index b99f171589..de2b712057 100644
--- a/acme/adders/reverb/structured.py
+++ b/acme/adders/reverb/structured.py
@@ -153,7 +153,7 @@ def add(self,
           extras: types.NestedArray = ()):
     """Record an action and the following timestep."""
 
-    if not self._writer.step_is_open:
+    if self._writer is None or not self._writer.step_is_open:
       raise ValueError('adder.add_first must be called before adder.add.')
 
     # Add the timestep to the buffer.