diff --git a/src/Database/Bloodhound/Types.hs b/src/Database/Bloodhound/Types.hs
index 0b11a40..d115246 100644
--- a/src/Database/Bloodhound/Types.hs
+++ b/src/Database/Bloodhound/Types.hs
@@ -1825,12 +1825,12 @@ instance ToJSON Query where
     object [ "common" .= commonTermsQuery ]
 
   toJSON (ConstantScoreFilter csFilter boost) =
-    object [ "constant_score" .= csFilter
+    object ["filter" .= object ["constant_score" .= csFilter]
            , "boost" .= boost]
 
   toJSON (ConstantScoreQuery query boost) =
-    object [ "constant_score" .= query
-           , "boost"          .= boost]
+    object ["query" .= object ["constant_score" .= query]
+           , "boost" .= boost]
 
   toJSON (QueryDisMaxQuery disMaxQuery) =
     object [ "dis_max" .= disMaxQuery ]
@@ -1926,10 +1926,15 @@ instance FromJSON Query where
           queryBoolQuery = pure . QueryBoolQuery
           queryBoostingQuery = pure . QueryBoostingQuery
           queryCommonTermsQuery = pure . QueryCommonTermsQuery
-          constantScoreFilter o = ConstantScoreFilter <$> o .: "constant_score"
-                                                      <*> o .: "boost"
-          constantScoreQuery o = ConstantScoreQuery <$> o .: "constant_score"
+          --FIXME: these are ambiguous
+          constantScoreFilter o = case HM.lookup "filter" o of
+            Just (Object o') -> ConstantScoreFilter <$> o' .: "constant_score"
                                                     <*> o .: "boost"
+            _ -> fail "Does not appear to be a ConstantScoreFilter"
+          constantScoreQuery o = case HM.lookup "query" o of
+            Just (Object o') -> ConstantScoreQuery <$> o' .: "constant_score"
+                                                   <*> o .: "boost"
+            _ -> fail "Does not appear to be a ConstantScoreFilter"
           queryDisMaxQuery = pure . QueryDisMaxQuery
           queryFilteredQuery = pure . QueryFilteredQuery
           queryFuzzyLikeThisQuery = pure . QueryFuzzyLikeThisQuery
diff --git a/tests/tests.hs b/tests/tests.hs
index 5034abf..28f6686 100644
--- a/tests/tests.hs
+++ b/tests/tests.hs
@@ -351,6 +351,56 @@ instance Arbitrary RegexpFlags where
 instance Arbitrary IndexAliasCreate where
   arbitrary = IndexAliasCreate <$> arbitrary <*> reduceSize arbitrary
 
+instance Arbitrary Query where
+  arbitrary = reduceSize $ oneof [ TermQuery <$> arbitrary <*> arbitrary
+                                 , TermsQuery <$> arbitrary <*> arbitrary
+                                 , QueryMatchQuery <$> arbitrary
+                                 , QueryMultiMatchQuery <$> arbitrary
+                                 , QueryBoolQuery <$> arbitrary
+                                 , QueryBoostingQuery <$> arbitrary
+                                 , QueryCommonTermsQuery <$> arbitrary
+                                 , ConstantScoreFilter <$> arbitrary <*> arbitrary
+                                 , ConstantScoreQuery <$> arbitrary <*> arbitrary
+                                 , QueryDisMaxQuery <$> arbitrary
+                                 , QueryFilteredQuery <$> arbitrary
+                                 , QueryFuzzyLikeThisQuery <$> arbitrary
+                                 , QueryFuzzyLikeFieldQuery <$> arbitrary
+                                 , QueryFuzzyQuery <$> arbitrary
+                                 , QueryHasChildQuery <$> arbitrary
+                                 , QueryHasParentQuery <$> arbitrary
+                                 , IdsQuery <$> arbitrary <*> arbitrary
+                                 , QueryIndicesQuery <$> arbitrary
+                                 , MatchAllQuery <$> arbitrary
+                                 , QueryMoreLikeThisQuery <$> arbitrary
+                                 , QueryMoreLikeThisFieldQuery <$> arbitrary
+                                 , QueryNestedQuery <$> arbitrary
+                                 , QueryPrefixQuery <$> arbitrary
+                                 , QueryQueryStringQuery <$> arbitrary
+                                 , QuerySimpleQueryStringQuery <$> arbitrary
+                                 , QueryRangeQuery <$> arbitrary
+                                 , QueryRegexpQuery <$> arbitrary
+                                 ]
+
+instance Arbitrary Filter where
+  arbitrary = reduceSize $ oneof [ AndFilter <$> arbitrary <*> arbitrary
+                                 , OrFilter <$> arbitrary <*> arbitrary
+                                 , NotFilter <$> arbitrary <*> arbitrary
+                                 , pure IdentityFilter
+                                 , BoolFilter <$> arbitrary
+                                 , ExistsFilter <$> arbitrary
+                                 , GeoBoundingBoxFilter <$> arbitrary
+                                 , GeoDistanceFilter <$> arbitrary <*> arbitrary <*> arbitrary <*> arbitrary <*> arbitrary
+                                 , GeoDistanceRangeFilter <$> arbitrary <*> arbitrary
+                                 , GeoPolygonFilter <$> arbitrary <*> arbitrary
+                                 , IdsFilter <$> arbitrary <*> arbitrary
+                                 , LimitFilter <$> arbitrary
+                                 , MissingFilter <$> arbitrary <*> arbitrary <*> arbitrary
+                                 , PrefixFilter <$> arbitrary <*> arbitrary <*> arbitrary
+                                 , QueryFilter <$> arbitrary <*> arbitrary
+                                 , RangeFilter <$> arbitrary <*> arbitrary <*> arbitrary <*> arbitrary
+                                 , RegexpFilter <$> arbitrary <*> arbitrary <*> arbitrary <*> arbitrary <*> arbitrary <*> arbitrary
+                                 , TermFilter <$> arbitrary <*> arbitrary]
+
 $(derive makeArbitrary ''IndexName)
 $(derive makeArbitrary ''MappingName)
 $(derive makeArbitrary ''DocId)
@@ -394,8 +444,6 @@ $(derive makeArbitrary ''PhraseSlop)
 $(derive makeArbitrary ''MinDocFrequency)
 $(derive makeArbitrary ''MaxDocFrequency)
 $(derive makeArbitrary ''Regexp)
-$(derive makeArbitrary ''Filter)
-$(derive makeArbitrary ''Query)
 $(derive makeArbitrary ''SimpleQueryStringQuery)
 $(derive makeArbitrary ''FieldOrFields)
 $(derive makeArbitrary ''SimpleQueryFlag)