diff --git a/openslides/agenda/views.py b/openslides/agenda/views.py
index 3d2d143f2..48898237d 100644
--- a/openslides/agenda/views.py
+++ b/openslides/agenda/views.py
@@ -59,19 +59,19 @@ class ItemViewSet(ListModelMixin, RetrieveModelMixin, UpdateModelMixin, GenericV
 
     def update(self, *args, **kwargs):
         """
-        Customized view endpoint to update all children if, the item type has changed.
+        Customized view endpoint to update all children if the item type has changed.
         """
         old_type = self.get_object().type
 
-        result = super().update(*args, **kwargs)
+        response = super().update(*args, **kwargs)
 
-        # update all children, if the item type has changed
+        # Update all children if the item type has changed.
         item = self.get_object()
 
         if old_type != item.type:
             items_to_update = []
 
-            # rekursively add children to items_to_update
+            # Recursively add children to items_to_update.
             def add_item(item):
                 items_to_update.append(item)
                 for child in item.children.all():
@@ -80,7 +80,7 @@ class ItemViewSet(ListModelMixin, RetrieveModelMixin, UpdateModelMixin, GenericV
             add_item(item)
             inform_changed_data(items_to_update)
 
-        return result
+        return response
 
     @detail_route(methods=['POST', 'PATCH', 'DELETE'])
     def manage_speaker(self, request, pk=None):
diff --git a/openslides/motions/views.py b/openslides/motions/views.py
index af0132f03..e9699d709 100644
--- a/openslides/motions/views.py
+++ b/openslides/motions/views.py
@@ -21,6 +21,7 @@ from ..utils.rest_api import (
     GenericViewSet,
     ModelViewSet,
     Response,
+    ReturnDict,
     UpdateModelMixin,
     ValidationError,
     detail_route,
@@ -195,7 +196,12 @@ class MotionViewSet(ModelViewSet):
         inform_changed_data(new_users)
 
         headers = self.get_success_headers(serializer.data)
-        return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)
+        # Strip out response data so nobody gets unrestricted data.
+        data = ReturnDict(
+            id=serializer.data.get('id'),
+            serializer=serializer
+        )
+        return Response(data, status=status.HTTP_201_CREATED, headers=headers)
 
     def update(self, request, *args, **kwargs):
         """
@@ -256,7 +262,8 @@ class MotionViewSet(ModelViewSet):
         new_users = list(updated_motion.supporters.all())
         inform_changed_data(new_users)
 
-        return Response(serializer.data)
+        # We do not add serializer.data to response so nobody gets unrestricted data here.
+        return Response()
 
     @list_route(methods=['post'])
     def sort(self, request):
@@ -636,10 +643,10 @@ class MotionPollViewSet(UpdateModelMixin, DestroyModelMixin, GenericViewSet):
         """
         Customized view endpoint to update a motion poll.
         """
-        result = super().update(*args, **kwargs)
+        response = super().update(*args, **kwargs)
         poll = self.get_object()
         poll.motion.write_log([ugettext_noop('Vote updated')], self.request.user)
-        return result
+        return response
 
     def destroy(self, *args, **kwargs):
         """
diff --git a/openslides/utils/rest_api.py b/openslides/utils/rest_api.py
index f1886bfdd..36a9f3b72 100644
--- a/openslides/utils/rest_api.py
+++ b/openslides/utils/rest_api.py
@@ -6,13 +6,14 @@ from rest_framework import status
 from rest_framework.decorators import detail_route, list_route
 from rest_framework.metadata import SimpleMetadata
 from rest_framework.mixins import (
-    CreateModelMixin,
+    CreateModelMixin as _CreateModelMixin,
     DestroyModelMixin,
     ListModelMixin as _ListModelMixin,
     RetrieveModelMixin as _RetrieveModelMixin,
-    UpdateModelMixin,
+    UpdateModelMixin as _UpdateModelMixin,
 )
 from rest_framework.relations import MANY_RELATION_KWARGS
+from rest_framework.request import Request
 from rest_framework.response import Response
 from rest_framework.routers import DefaultRouter
 from rest_framework.serializers import (
@@ -33,10 +34,10 @@ from rest_framework.serializers import (
     SerializerMethodField,
     ValidationError,
 )
+from rest_framework.utils.serializer_helpers import ReturnDict
 from rest_framework.viewsets import (
     GenericViewSet as _GenericViewSet,
     ModelViewSet as _ModelViewSet,
-    ViewSet as _ViewSet,
 )
 
 from .access_permissions import BaseAccessPermissions
@@ -44,8 +45,8 @@ from .auth import user_to_collection_user
 from .collection import Collection, CollectionElement
 
 
-__all__ = ['detail_route', 'DecimalField', 'list_route', 'SimpleMetadata', 'CreateModelMixin',
-           'DestroyModelMixin', 'UpdateModelMixin', 'CharField', 'DictField', 'FileField',
+__all__ = ['detail_route', 'DecimalField', 'list_route', 'SimpleMetadata',
+           'DestroyModelMixin', 'CharField', 'DictField', 'FileField',
            'IntegerField', 'JSONField', 'ListField', 'ListSerializer', 'status', 'RelatedField',
            'SerializerMethodField', 'ValidationError']
 
@@ -237,13 +238,44 @@ class RetrieveModelMixin(_RetrieveModelMixin):
         return response
 
 
+class CreateModelMixin(_CreateModelMixin):
+    """
+    Mixin to override create requests.
+    """
+    def create(self, request: Request, *args: Any, **kwargs: Any) -> Response:
+        """
+        Just remove all response data (except 'id') so nobody may get
+        unrestricted data.
+
+        Special viewsets may override this.
+        """
+        response = super().create(request, *args, **kwargs)
+        response.data = ReturnDict(
+            id=response.data.get('id'),
+            serializer=response.data.serializer  # This kwarg is not send to the client.
+        )
+        return response
+
+
+class UpdateModelMixin(_UpdateModelMixin):
+    """
+    Mixin to override update requests.
+    """
+    def update(self, request: Request, *args: Any, **kwargs: Any) -> Response:
+        """
+        Just remove all response data so nobody may get unrestricted data.
+
+        Special viewsets may override this.
+        """
+        response = super().update(request, *args, **kwargs)
+        response.data = None
+        return response
+
+
 class GenericViewSet(PermissionMixin, _GenericViewSet):
     pass
 
 
-class ModelViewSet(PermissionMixin, ListModelMixin, RetrieveModelMixin, _ModelViewSet):
-    pass
-
-
-class ViewSet(PermissionMixin, _ViewSet):
+class ModelViewSet(PermissionMixin, ListModelMixin, RetrieveModelMixin,
+                   CreateModelMixin, UpdateModelMixin, _ModelViewSet):
     pass