The problem here is the fact that sexual assault cases are treated much differently than any other crime by the public.  Just being accused, not even charged, is enough to ruin a man's life forever.  Because of that, we should be very careful when proceeding with this (as we can expect the government to go all "bull in a china shop" anyway).

If someone is convicted of sexual assault then they should be punished in the appropriate fashion.  Until that time, there absolutely need to protections for the accused, as well as the accusers.

I think part of the reason police tread so carefully on these files is because they know how much damage they will be doing just investigating the charges.