Joplin police are not identifying the motorist who saw a hit-and-run driver run over a teenage girl…then followed the car and kept police informed on his cell phone of where it was going. Officers followed the directions and made the arrest. Officers saya the driver of the hit-and-run car might have been drunk. 17-year-old Laura Williams was killed. The man suspected of driving the car that hit her is charged with manslaughter.