Harris County Sheriff’s Deputies say Emil McMahon killed a driver in Baytown while attempting to run his wife off of the road  Sunday morning.  Just before 11:00am the husband and wife were driving separate vehicles on FM 1943 when McMahon tried to force his wife off the road because of an earlier dispute. Investigators say as he was maneuvering his pickup truck, he collided head-on with another vehicle.  The driver, Tania M. Vercher of Baytown,  was killed and her preschool-age son was severely injured. At last check the boy is listed in critical condition at Memorial Hermann Texas Medical Center hospital.  McMahon's charges are pending the results of a blood test.  HCSO officials said McMahon’s wife did not suffer any serious injuries.