On July 17, 1995, at 2155 hours Pacific daylight time, a Embraer EMB-120RT, N268UE, collided with a parked Boeing 767-222, N612UA, on the United Airlines maintenance ramp at Los Angeles International Airport, Los Angeles, California. The airplane was being operated by West Air Commuter Airlines, Inc., dba United Express, as a scheduled domestic passenger flight under 14 CFR Part 135. The commuter airplane was substantially damaged. There were no injuries to the three crewmembers or to the three passengers. The flight was destined for Palm Springs, California. Night visual meteorological conditions prevailed. The ramp area lease holder is United Airlines. United Airlines allocates space to United Express to operate a Commuter Air Terminal and park their aircraft. According to agreements with the airport authorities, movement of aircraft within the leasehold is the responsibility of the operator and is done without air traffic control clearance or guidance. A taxiway was designated by the lease holder for the movement of United Express aircraft to the edge of the ramp area at taxiway 27K and taxiway 19K. The leasehold taxiway provided clearance for United Express aircraft while gaining access to airport taxiways and runways. The taxiway was marked with yellow centerline and taxiway edge stripping. The width of the taxiway was sufficient for a towed Boeing 737 aircraft to clear other aircraft parked in designated numbered spots. A diagram of the taxiway was provided by the leaseholder, United Airlines, to United Express and to Los Angeles International Airport operations. The captain of the Embraer EMB-120RT elected to taxi in a non- movement area and did not use the designated taxiway. The United Express captain told the Safety Board her decision was based on avoiding a delay as a result of encountering a possible conflict with any aircraft being towed for maintenance while gaining access at taxiway 19K. A construction project had closed the taxiway 27K, which was normally used to exit the ramp. The captain planned to use taxiway 23K further to the east by taxiing behind a row of Boeing 737 aircraft. The captain was taxing behind the row of parked Boeing 737 aircraft, between the row and an airport access road. A Boeing 767 was parked at the east end of the row near the area where the taxiway joins the ramp. The captain indicated the Embraer's right wing was close to the access road. After the nose of the Embraer cleared the tail of the Boeing 767, the captain turned left towards the Boeing 767 and away from the access road. The left horizontal stabilizer of the Embraer then collided with the bottom of the right elevator on the Boeing 767, twisting the vertical stabilizer on the Embraer about 30 degrees counterclockwise.