You can verify compliance with image usage rules with the Images button for a competition.
If you have polices related to re-using images in different competitions you will need to manually audit compliance. Creating a system to force compliance would be complex due to the many exceptions and complex configurations required.
An easier path is to audit compliance. Use a Manage Competitions page and the Images button. The page that displays includes a column for "Other Uses". You can review images that have been used elsewhere to determine if you have a policy violation. That list can also be exported to Excel, if desired.