Madison police are investigating why the driver of an SUV served into oncoming traffic on the city's Far West Side Monday night. The driver, a 44 year old Madison woman, is hospitalized in critical condition. The crash happened at the intersection of North Gammon and Old Sauk roads, just before 8 p.m. The site wasn't re-opened to traffic until about 2 a.m. Tuesday. The other drivers involved were not seriously hurt.