A method for detecting potential money-laundering activities or other illegal activities in the use of a gaming accounting system includes collecting data regarding a player's activity in a gaming system. The gaming system activity data is collected in terms of a gaming activity network, that is, a series of linked activities or events, and/or objects associated with activities or events. In response to a predefined event such as a cash out or credit redemption transaction request initiated by the player, the method includes evaluating the collected data to identify potentially illegal or prohibited activity. In the event illegal activity is indicated, the method includes taking some corrective action such as producing an operator alert to the potential illegal activity.