diff --git a/aleksis/core/util/auth_helpers.py b/aleksis/core/util/auth_helpers.py
index fe19f49de00eb0b3a7d677a12d4e78117fdd79a6..4b19d475ebf40ca5bdacaaaef3622f5a303fb701 100644
--- a/aleksis/core/util/auth_helpers.py
+++ b/aleksis/core/util/auth_helpers.py
@@ -82,7 +82,9 @@ class CustomOAuth2Validator(OAuth2Validator):
             }
 
         if "groups" in request.scopes and has_person(request.user):
-            claims["groups"] = request.user.person.member_of.values_list("name", flat=True).all()
+            claims["groups"] = list(
+                request.user.person.member_of.values_list("name", flat=True).all()
+            )
 
         return claims