diff --git a/arangod/Aql/Functions.cpp b/arangod/Aql/Functions.cpp
index 296e104db8..824eed42ea 100644
--- a/arangod/Aql/Functions.cpp
+++ b/arangod/Aql/Functions.cpp
@@ -1544,8 +1544,7 @@ AqlValue Functions::Attributes(arangodb::aql::Query* query,
   VPackBuilder result;
   result.openArray();
   for (auto const& it : keys) {
-    TRI_ASSERT(!it.empty());
-    if (removeInternal && it.at(0) == '_') {
+    if (removeInternal && !it.empty() && it.at(0) == '_') {
       continue;
     }
     result.add(VPackValue(it));