Two things here:
First, apparently women are getting pulled over by men pretending to be police officers in unmarked cars.
"In February, three women reported being sexually assaulted after being pulled over by men who identified themselves as cops and drove police-style cars with flashing lights. Another woman reported a similar sexual assault in October.
Some of the men flashed badges, and one wore a gun, but authorities say they all were imposters." (source)
On the news the other day they said if you are nervous about the car that is pulling you over put on your hazard lights and call 911 to inquire about the validity of the stop.
National Summary has an interesting piece about women getting pulled over -in regards to getting out of tickets. Almost all the cops I know (except Free) will let a woman off if she cries...drop the pride ladies. I must say, I have no problem using the reverse discrimination and have been pulled over many times and never gotten a ticket (thankfully I've never been pulled over by a woman!)