Abstract: A computer-implemented fraud detection method and system for periodically identifying network associations in a consumer population at a national credit reporting agency and computing associated network level variables related to credit use and potential first party fraud for the consumer population. In response to receiving a request for a target account from among the consumer population the computer-implemented system retrieves credit report for the target account and computes tradeline or account level variables related to credit use and potential fraudulent behavior. A fraud score is calculated based on a combined evaluation of the network level variables and the tradeline or account level variables.