diff --git a/lib/Db/Acl.php b/lib/Db/Acl.php
index d977f3f06..f4355ade8 100644
--- a/lib/Db/Acl.php
+++ b/lib/Db/Acl.php
@@ -82,11 +82,7 @@ class Acl extends RelationalEntity implements \JsonSerializable {
 			'owner' => $this->getOwner()
 		];
 	}
-
-	/*
-	 * FIXME: migrate other code to const PERMISSION_TYPE_ instead of strings
-	 * iirc js uses those strings as well
-	 */
+	
 	public function getTypeString() {
 		if ($this->type === Acl::PERMISSION_TYPE_GROUP) {
 			return 'group';
diff --git a/lib/Service/PermissionService.php b/lib/Service/PermissionService.php
index ca1badae5..bd3985a51 100644
--- a/lib/Service/PermissionService.php
+++ b/lib/Service/PermissionService.php
@@ -127,14 +127,14 @@ class PermissionService {
 	public function userCan(array $acls, $permission) {
 		// check for users
 		foreach ($acls as $acl) {
-			if ($acl->getType() === "user" && $acl->getParticipant() === $this->userId) {
+			if ($acl->getType() === Acl::PERMISSION_TYPE_USER && $acl->getParticipant() === $this->userId) {
 				return $acl->getPermission($permission);
 			}
 		}
 		// check for groups
 		$hasGroupPermission = false;
 		foreach ($acls as $acl) {
-			if (!$hasGroupPermission && $acl->getType() === "group" && $this->groupManager->isInGroup($this->userId, $acl->getParticipant())) {
+			if (!$hasGroupPermission && $acl->getType() === Acl::PERMISSION_TYPE_GROUP && $this->groupManager->isInGroup($this->userId, $acl->getParticipant())) {
 				$hasGroupPermission = $acl->getPermission($permission);
 			}
 		}