diff --git a/lib/experimental/class-gutenberg-rest-comment-controller.php b/lib/experimental/class-gutenberg-rest-comment-controller.php
index 8409c595032..bf2bdee9cc7 100644
--- a/lib/experimental/class-gutenberg-rest-comment-controller.php
+++ b/lib/experimental/class-gutenberg-rest-comment-controller.php
@@ -110,8 +110,20 @@ class Gutenberg_REST_Comment_Controller extends WP_REST_Comments_Controller {
 			);
 		}
 
+		if ( comments_open( $post->ID ) ) {
+			return new WP_Error(
+				'rest_comments_closed',
+				__( 'Sorry, comments are closed for this post.', 'gutenberg' ),
+				array( 'status' => 403 )
+			);
+		}
+
 		return true;
 	}
+
+	protected function check_edit_permission( $comment ) {
+		return false;
+	}
 }
 
 add_action(