Systems and methods are provided for use in identifying synthetic identities. One example method includes receiving a request from a relying party for an identity asserted by a user to the relying party, where the request includes identity data indicative of the identity, feature data associated with the user asserting the identity, and a device ID for a communication device of the user. The method also includes parsing the identity data, the feature data, and the device ID from the request, and calculating a device behavior score based on the feature data and the device ID. The method then includes aggregating the device behavior score and at least one of a fraud profile score, a user profile score, and/or an exposure behavior score into a metric indicative of a likelihood that the identity asserted by the user is a synthetic identity and transmitting the metric to the relying party.