diff --git a/polytope_server/common/authentication/authentication.py b/polytope_server/common/authentication/authentication.py
index 51546dd..67a589b 100644
--- a/polytope_server/common/authentication/authentication.py
+++ b/polytope_server/common/authentication/authentication.py
@@ -77,7 +77,7 @@ def name(self) -> str:
     "plain": "PlainAuthentication",
     "keycloak": "KeycloakAuthentication",
     "federation": "FederationAuthentication",
-    "jwt" : "JWTBearerAuthentication",
+    "jwt" : "JWTAuthentication",
 }
 
 
diff --git a/polytope_server/common/authentication/jwt_bearer_authentication.py b/polytope_server/common/authentication/jwt_authentication.py
similarity index 70%
rename from polytope_server/common/authentication/jwt_bearer_authentication.py
rename to polytope_server/common/authentication/jwt_authentication.py
index e20e3a6..47e49bb 100644
--- a/polytope_server/common/authentication/jwt_bearer_authentication.py
+++ b/polytope_server/common/authentication/jwt_authentication.py
@@ -26,9 +26,10 @@
 from ..auth import User
 from ..caching import cache
 from . import authentication
+from ..exceptions import ForbiddenRequest
 
 
-class JWTBearerAuthentication(authentication.Authentication):
+class JWTAuthentication(authentication.Authentication):
     def __init__(self, name, realm, config):
         self.config = config
 
@@ -48,16 +49,21 @@ def get_certs(self):
 
     @cache(lifetime=120)
     def authenticate(self, credentials: str) -> User:
-        certs = self.get_certs()
-        decoded_token = jwt.decode(token=credentials,
-            algorithms=jwt.get_unverified_header(credentials).get('alg'),
-            key=certs
-        )
 
-        user = User(decoded_token["sub"], self.realm())
+        try:
+            certs = self.get_certs()
+            decoded_token = jwt.decode(token=credentials,
+                algorithms=jwt.get_unverified_header(credentials).get('alg'),
+                key=certs
+            )
 
-        logging.debug("Found user {} from decoded JWT".format(user))
+            user = User(decoded_token["sub"], self.realm())
 
+            logging.info("Found user {} from decoded JWT".format(user))
+        except Exception as e:
+            logging.info("Failed to authenticate user from JWT")
+            logging.info(e)
+            raise ForbiddenRequest("Credentials could not be unpacked")
         return user
 
 
diff --git a/polytope_server/common/datasource/mars.py b/polytope_server/common/datasource/mars.py
index f949fa0..523c762 100644
--- a/polytope_server/common/datasource/mars.py
+++ b/polytope_server/common/datasource/mars.py
@@ -182,13 +182,13 @@ def make_env(self, request):
                 logging.info("Overriding MARS_USER_EMAIL with {}".format(self.override_mars_email))
                 mars_user = self.override_mars_email
             else:
-                mars_user = request.user.attributes["ecmwf-email"]
+                mars_user = request.user.attributes.get("ecmwf-email", "no-email")
 
             if self.override_mars_apikey:
                 logging.info("Overriding MARS_USER_TOKEN with {}".format(self.override_mars_apikey))
                 mars_token = self.override_mars_apikey
             else:
-                mars_token = request.user.attributes["ecmwf-apikey"]
+                mars_token = request.user.attributes.get("ecmwf-apikey", "no-api-key")
 
             env = {
                 **os.environ,