diff --git a/engine/ladon/handler.go b/engine/ladon/handler.go
index e3e7b3e02..174f715f9 100644
--- a/engine/ladon/handler.go
+++ b/engine/ladon/handler.go
@@ -290,8 +290,7 @@ func (e *Engine) Register(r *httprouter.Router) {
 }
 
 func (e *Engine) rolesList(ctx context.Context, r *http.Request, ps httprouter.Params) (*kstorage.ListRequest, error) {
-	var p kstorage.Roles
-
+	p := make(kstorage.Roles, 0)
 	f, err := flavor(ps)
 	if err != nil {
 		return nil, err
@@ -428,8 +427,8 @@ func (e *Engine) policiesCreate(ctx context.Context, r *http.Request, ps httprou
 }
 
 func (e *Engine) policiesList(ctx context.Context, r *http.Request, ps httprouter.Params) (*kstorage.ListRequest, error) {
-	var p kstorage.Policies
 
+	p := make(kstorage.Policies, 0)
 	f, err := flavor(ps)
 	if err != nil {
 		return nil, err
diff --git a/storage/filter_helper_test.go b/storage/filter_helper_test.go
index 8749fda8f..e8b9ff30d 100644
--- a/storage/filter_helper_test.go
+++ b/storage/filter_helper_test.go
@@ -52,7 +52,7 @@ var (
 				Members: []string{"mem1", "mem2"},
 			},
 		},
-		nil,
+		Roles{},
 		rolReq,
 		rolReq,
 		rolReq,
@@ -93,7 +93,7 @@ var (
 				Resources: []string{"res1", "res2"},
 			},
 		},
-		nil,
-		nil,
+		Policies{},
+		Policies{},
 	}
 )
diff --git a/storage/handler.go b/storage/handler.go
index 9949e1dee..6f3dc10c1 100644
--- a/storage/handler.go
+++ b/storage/handler.go
@@ -85,7 +85,7 @@ func (l *ListRequest) Filter(m map[string][]string) *ListRequest {
 func ListByQuery(l *ListRequest, m map[string][]string) {
 	switch val := l.Value.(type) {
 	case *Roles:
-		var res Roles
+		res := make(Roles, 0)
 		for _, role := range *val {
 			filteredRole := role.withMembers(m["member"]).withIDs(m["id"])
 			if filteredRole != nil {
@@ -94,7 +94,7 @@ func ListByQuery(l *ListRequest, m map[string][]string) {
 		}
 		l.Value = &res
 	case *Policies:
-		var res Policies
+		res := make(Policies, 0)
 		for _, policy := range *val {
 			filteredPolicy := policy.withSubjects(m["subject"]).withResources(m["resource"]).withActions(m["action"]).withIDs(m["id"])
 			if filteredPolicy != nil {