As admin, enable "Mobile services": Site administration ► Mobile app ► Mobile settings Create a course and inside the course a choice activity that allows changing response to the user ("Allow choice to be updated" option). Add one student and one teacher to the course Acces to the choice as the student and answer the choice. Do the same with the teacher Create a Token in the mobile app service for the teacher user: Click on Site administration ► Plugins ► Web services ► Manage tokens Now, via the Moodle Mobile app access to the choice as the teacher. Delete your response via the "Remove my choice" button. Check only your responses have been deleted. The student response should be still there. Next, you can do a CURL REST call simulating a WS client with the user. curl ' [YOUR_MOODLE_URL] /webservice/rest/server.php?moodlewsrestformat=json' --data 'choiceid= [CHOICE_ID] &responses [0] = [RESPONSE_ID] &moodlewssettingfilter=true&moodlewssettingfileurl=true&wsfunction=mod_choice_delete_choice_responses&wstoken= [WS_TOKEN] ' | python -m json.tool You need to replace the following parameters: " wstoken " with the teacher's WS token, " choiceid " with the choice instance id (from " choice " table) " responses [0] " with the ID of the student response (you can get if from the " choice_answers " table in the DB) the URL of your Moodle instance Now check in the app or on the site that the student response was deleted. If you execute the previous curl request but passing a " responses [0] " value that does not exist in the DB or that belongs to a different choice, you will get an exception "No permission to delete this response"