diff --git a/api/src/controllers/group.ts b/api/src/controllers/group.ts
index 9f6e41b..c5b8681 100644
--- a/api/src/controllers/group.ts
+++ b/api/src/controllers/group.ts
@@ -10,7 +10,7 @@ import {
   Body
 } from 'tsoa'
 
-import Group, { GroupPayload } from '../model/Group'
+import Group, { GroupPayload, PUBLIC_GROUP_NAME } from '../model/Group'
 import User from '../model/User'
 import { UserResponse } from './user'
 
@@ -241,6 +241,13 @@ const updateUsersListInGroup = async (
       message: 'Group not found.'
     }
 
+  if (group.name === PUBLIC_GROUP_NAME)
+    throw {
+      code: 400,
+      status: 'Bad Request',
+      message: `Can't add/remove user to '${PUBLIC_GROUP_NAME}' group.`
+    }
+
   const user = await User.findOne({ id: userId })
   if (!user)
     throw {
diff --git a/api/src/routes/api/spec/group.spec.ts b/api/src/routes/api/spec/group.spec.ts
index 86196ce..4b34e9e 100644
--- a/api/src/routes/api/spec/group.spec.ts
+++ b/api/src/routes/api/spec/group.spec.ts
@@ -5,6 +5,7 @@ import request from 'supertest'
 import appPromise from '../../../app'
 import { UserController, GroupController } from '../../../controllers/'
 import { generateAccessToken, saveTokensInDB } from '../../../utils'
+import { PUBLIC_GROUP_NAME } from '../../../model/Group'
 
 const clientId = 'someclientID'
 const adminUser = {
@@ -27,6 +28,12 @@ const group = {
   description: 'DC group for testing purposes.'
 }
 
+const PUBLIC_GROUP = {
+  name: PUBLIC_GROUP_NAME,
+  description:
+    'It is a special group that bypasses authentication for particular routes.'
+}
+
 const userController = new UserController()
 const groupController = new GroupController()
 
@@ -535,6 +542,24 @@ describe('group', () => {
       expect(res.text).toEqual('User not found.')
       expect(res.body).toEqual({})
     })
+
+    it('should respond with Bad Request when adding user to Public group', async () => {
+      const dbGroup = await groupController.createGroup(PUBLIC_GROUP)
+      const dbUser = await userController.createUser({
+        ...user,
+        username: 'publicUser'
+      })
+
+      const res = await request(app)
+        .post(`/SASjsApi/group/${dbGroup.groupId}/${dbUser.id}`)
+        .auth(adminAccessToken, { type: 'bearer' })
+        .send()
+        .expect(400)
+
+      expect(res.text).toEqual(
+        `Can't add/remove user to '${PUBLIC_GROUP_NAME}' group.`
+      )
+    })
   })
 
   describe('RemoveUser', () => {