diff --git a/swh/deposit/exception.py b/swh/deposit/exception.py
index 99fcf653..cdd1f7d0 100644
--- a/swh/deposit/exception.py
+++ b/swh/deposit/exception.py
@@ -1,34 +1,38 @@
 # Copyright (C) 2020  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 from typing import Dict, Optional
 
 from rest_framework.exceptions import APIException
-from rest_framework.response import Response
 from rest_framework.views import exception_handler
+from django.http import HttpResponse
 
 from django.db.utils import OperationalError
 
 
-def custom_exception_handler(exc: APIException, context: Dict) -> Optional[Response]:
+def custom_exception_handler(
+    exc: APIException, context: Dict
+) -> Optional[HttpResponse]:
     """Custom deposit exception handler to ensure consistent xml output
 
     """
     # drf's default exception handler first, to get the standard error response
     response = exception_handler(exc, context)
 
     if isinstance(exc, OperationalError):
         status = "Database backend maintenance"
         detail = "Service temporarily unavailable, try again later."
         data = f"""<?xml version="1.0" encoding="utf-8"?>
 <sword:error xmlns="http://www.w3.org/2005/Atom"
        xmlns:sword="http://purl.org/net/sword/">
     <summary>{status}</summary>
     <sword:verboseDescription>{detail}</sword:verboseDescription>
 </sword:error>
-"""
-        return Response(data, status=503, content_type="application/xml")
+""".encode(
+            "utf-8"
+        )
+        return HttpResponse(data, status=503, content_type="application/xml")
 
     return response
diff --git a/swh/deposit/tests/api/test_exception.py b/swh/deposit/tests/api/test_exception.py
index 91272cfc..0d71926b 100644
--- a/swh/deposit/tests/api/test_exception.py
+++ b/swh/deposit/tests/api/test_exception.py
@@ -1,54 +1,53 @@
 # Copyright (C) 2020 The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 from swh.deposit.exception import custom_exception_handler
 
 from rest_framework.exceptions import APIException
 from rest_framework.response import Response
 
 from django.db.utils import OperationalError
 
 
 def test_custom_exception_handler_operational_error(mocker):
     """Operation error are translated to service unavailable
 
     """
     fake_exception = OperationalError("Fake internal error", 503)
 
     response = custom_exception_handler(fake_exception, {})
 
     assert response is not None
-    assert response.content_type == "application/xml"
     assert response.status_code == 503
 
     status = "Database backend maintenance"
     detail = "Service temporarily unavailable, try again later."
     assert (
-        response.data
+        response.content.decode("utf-8")
         == f"""<?xml version="1.0" encoding="utf-8"?>
 <sword:error xmlns="http://www.w3.org/2005/Atom"
        xmlns:sword="http://purl.org/net/sword/">
     <summary>{status}</summary>
     <sword:verboseDescription>{detail}</sword:verboseDescription>
 </sword:error>
 """
     )
 
 
 def test_custom_exception_handler_default_behavior_maintained(mocker):
     """Other internal errors are transmitted as is
 
     """
     fake_exception = APIException("Fake internal error", 500)
     fake_response = Response(
         exception=fake_exception, status=fake_exception.status_code
     )
     mock_exception_handler = mocker.patch("swh.deposit.exception.exception_handler")
     mock_exception_handler.return_value = fake_response
 
     response = custom_exception_handler(fake_exception, {})
 
     assert response is not None
     assert response == fake_response