Can you disable lights and shadows from being included in the render from a second camera for the purposes of a minimap?

Might be an easy fix, but a bit of a head scratcher for me. I have set up a scene which uses a GI based day/night system and have got a minimap up and running. However, I need to find a way to disable shadows and lighting changes from affecting the minimap camera only. Any ideas anyone? Help would be very much appreciated!