I agreed that interpreters should dress professionally since it is a job after all. One thing about the picture, I don't think interpreter should wear mini skirts or any skirts above the knee. Maybe it won't bother the deaf client but it can be distracting for others who can probably see "underneath." :roll:
Skirts lengths that pass the knee should be okay.
Interpreter should dress to blend in the environment such as the college university. I had a professor who came to class teaching with flip flops, beach shorts, and tie dye shirts. 
I know I would feel out of place if the interpreter showed up too professionally dress for that class.
