The trial in a San Diego traffic court could help shape future laws on wearable technology as it goes mainstream.
Software developer Cecilia Abadie is among 30,000 people called "explorers" who were selected to try out the device, known as Google Glass, before the technology becomes widely available to the public later this year.
The device on a specially designed spectacle frame features a thumbnail-size transparent display above the right eye.
Abadie was pulled over in October. She has pleaded not guilty. Her lawyer William Concidine said the device was not activated when she was driving.