Abstract: A social networking system validates content items based on policies regarding use of content items. The social networking system balances the validation process of content items with at least two validation queues, each having a priority value and some number of content items. A validation queue is selected based on the priority values. From the selected validation queue, a content item is determined to be valid or invalid. A validation efficiency for each queue is calculated based on the validated content items from each queue. The social networking system dynamically adjusts the priority value of each queue based on the validation efficiencies. The dynamic adjustment may be periodic. The social networking system may withhold invalid content items from users.