All depends on the situation. Seems to me police like to hear a female voice meaning female dispatchers.
I recall years ago reading a story of how NATO used to monitor the radio transmissions of Soviet pilots. They were listening to one conversation where the pilot was clearly having trouble with the airplane, while a recorded female voice kept calling out the altitude in sultry tones. "Fifteen thousand feet ... ten thousand feet ... five thousand feet ...." At the very end the pilot cried out, "Shutup, bitch, don't tell me how to fly an airplane!" Then there was silence.
There are times when a female voice on the radio net is easier to hear and understand. Has to be the right female voice, though. Maturity helps.