diff --git a/src/backend.memory.js b/src/backend.memory.js
index c1cf8dcf..6fcdc5ee 100644
--- a/src/backend.memory.js
+++ b/src/backend.memory.js
@@ -109,7 +109,12 @@ this.recline.Backend.Memory = this.recline.Backend.Memory || {};
             var foundmatch = false;
             _.each(self.fields, function(field) {
               var value = rawdoc[field.id];
-              if (value !== null) { value = value.toString(); }
+              if (value !== null) { 
+                value = value.toString();
+              } else {
+                // value can be null (apparently in some cases)
+                value = '';
+              }
               // TODO regexes?
               foundmatch = foundmatch || (value.toLowerCase() === term.toLowerCase());
               // TODO: early out (once we are true should break to spare unnecessary testing)