In an online marketplace, buyers and sellers engage in transactions. Some transactions are fraudulent. The online marketplace uses a fraud detection system that identifies fraudulent transactions before an account holder is defrauded. In some example embodiments of the systems and methods described herein, a fraud detection system uses information that is indirectly associated with a transaction to determine if the transaction is fraudulent. A user interface is provided that shows relationships between accounts and objects. In response to input received via the user interface, the fraud detection system performs an action on an account, an object, or a transaction.