The woman says she saw flashing lights in her rearview mirror and pulled over.
The victim told investigators that the suspect was dressed in a dark uniform with a badge and said he stopped her because she was swerving on the road.
He asked her for identification and told her to get out of her car and ordered her to take a field sobriety test.
She said he then told her to put her hands on the trunk of her ca, and then began to grope her.
The woman says she was able to break free after fighting with the man.
The suspect is described as a Hispanic in his 30s, about 5 feet 10 inches and 185 pounds. He was driving a dark colored Ford, possibly a Crown Victoria, with spotlights and a forward flashing blue light.
The woman was treated for injuries and released.