diff --git a/openstack/identity/v2/extensions/admin/roles/results.go b/openstack/identity/v2/extensions/admin/roles/results.go
index 6cfe3ac..608f206 100644
--- a/openstack/identity/v2/extensions/admin/roles/results.go
+++ b/openstack/identity/v2/extensions/admin/roles/results.go
@@ -1,7 +1,6 @@
 package roles
 
 import (
-	"github.com/mitchellh/mapstructure"
 	"github.com/gophercloud/gophercloud"
 	"github.com/gophercloud/gophercloud/pagination"
 )
@@ -29,21 +28,17 @@
 // IsEmpty determines whether or not a page of Tenants contains any results.
 func (page RolePage) IsEmpty() (bool, error) {
 	users, err := ExtractRoles(page)
-	if err != nil {
-		return false, err
-	}
-	return len(users) == 0, nil
+	return len(users) == 0, err
 }
 
 // ExtractRoles returns a slice of roles contained in a single page of results.
 func ExtractRoles(page pagination.Page) ([]Role, error) {
-	casted := page.(RolePage).Body
-	var response struct {
-		Roles []Role `mapstructure:"roles"`
+	r := page.(RolePage)
+	var s struct {
+		Roles []Role `json:"roles"`
 	}
-
-	err := mapstructure.Decode(casted, &response)
-	return response.Roles, err
+	err := r.ExtractInto(&s)
+	return s.Roles, err
 }
 
 // UserRoleResult represents the result of either an AddUserRole or