diff --git a/src/main/webapp/src/app/model/groupLeader.ts b/src/main/webapp/src/app/model/groupLeader.ts
index 02d3130..4a43509 100644
--- a/src/main/webapp/src/app/model/groupLeader.ts
+++ b/src/main/webapp/src/app/model/groupLeader.ts
@@ -1,9 +1,9 @@
 export class GroupLeader {
-  id: number;
+  id: number | null;
   personId: number;
-  groupId: number;
+  groupId: number | null;
 
-  constructor(id: number, personId: number, groupId: number) {
+  constructor(id: number | null, personId: number, groupId: number | null) {
     this.id = id;
     this.personId = personId;
     this.groupId = groupId;