A method and system for controlling location-determination in a wireless communication system. A rules engine can be positioned in a communication path between a location-based service (such as a PSAP) and a location-determination system (such as an MPC) and can cache the location of a wireless communication device as determined by the location-determination system. The next time the location-based service sends a position request to the location-determination system, the rules engine can then intercept the request and provide the cached location in a response without passing the request along to the location-determination system. In another embodiment, a rules engine external to a location-determination system can push logic to the location-determination system, to cause the location-determination system to carry out useful functions such as determining if a wireless communication device is fixed or mobile, setting a cache timer, and/or setting an overlap threshold for use in an overlapping circles analysis.