Check whether the following link is useful for your situation.
I would create a parameter with those 3 options. For the example lets say Live, Sim and Erich are in a field call Category. Then create a calculated field based on what option is chosen like:
iif(parameter='Where',[category], iif(parameter='Called By', [e/m], iif(parameter='P/L',[p/l],'')))
then drag that calculated field onto the color shelf.