Disable judges from scoring a video twice

Hi Oscar, I am a laravel developer and presently working on a project which I am almost done but stuck at some point I can no longer crack. The project as to do with uploading of video to different categories, likewise we have different adjudicators in those categories. Adjudicators have a panel where they can log in see as to see their category videos and score it. I am using a one to many relationship for the adjudicator and the video because a video can be scored by more than one adjudicator in that category. Problem statement : How do I tell the app that the current user have scored a particular video.

Looking forward to your kind response

Thanks