Motorcyclist's death after a double collision

In this accident there is a motorcyclist heading south on Highway 67, when a car turns left of center attempting to turn into a driveway when the two collide. The motorcyclist then careens off of the first car and into another vehicle heading north. There are several questions that immediately come to mind and may shed light on whether one, two or three drivers are at fault.

It might be easy to determine how close the third vehicle was following the first vehicle. This is important because if you add distance, by slowing the speed of car number  three and the head-on collision can't happen.

The second set of questions is about car number two. The car turning left of center with the duty to yield is a 2005 Pontiac Bonneville being driven by a 45-year-old woman; she was cited for operating while intoxicated, 1^st offense under 321J.2(2A).  Her car was struck in the right rear, which would seem to indicate the motorcyclist attempted to avoid the collision.

The third set of questions will have to do with the speed of the cyclist; although knowing the second driver turned left of center is enough to find her at-fault. If they can prove she was drinking the case of fault is pretty much wrapped up against her.

THE FACTS
Accident location is ¾ miles north of LeClaire on US Highway 67 (Great River Road between 217^th Street Place and 218^th Street in Scott County, Iowa.

Date of Accident: 8/22/2010 at 5:26 pm.

Motorcyclist: John Clifford from Galesburg, Illinois was wearing a helmet and is listed as fatal.  He was 55-years-old. No charges were filed against him.

The third vehicle is a 1993 240 SX driven by a 24-year-old man from Betterndorf. He was also not cited.

An injured passenger was Kathy Clifford, a 53-year-old woman who was on the motorcycle and taken to Genesis East by EMS. She too was wearing her helmet.

Here is Trooper Pedersen's narrative: UNIT 1 WAS NORTHBOUND ON HIGHWAY 67 TURNING LEFT INTO A DRIVEWAY AT 21742 HIGHWAY 67, WHICH IS A RESIDENCE ON THE WEST SIDE OF THE HIGHWAY. UNIT 2 WAS SOUTHBOUND ON HIGHWAY 67 APPROACHING THE DRIVEWAY INTERSECTION FROM THE NORTH. UNIT 3 WAS NORTHBOUND BEHIND UNIT 1. UNIT 1 TURNED INTO THE PATH OF UNIT 2, AND UNIT 1 AND UNIT 2 COLLIDED IN THE SOUTHBOUND LANE. UNIT 2 WENT INTO THE NORTHBOUND LANE AFTER THE INITIAL IMPACT AND STRUCK THE FRONT OF UNIT 3, WHICH WAS STOPPED. UNIT 2 CAME TO REST ON ITS SIDE IN THE CENTER OF THE NORTHBOUND LANE IN FRONT OF UNIT 3. UNIT 1 CAME TO REST IN THE DRIVEWAY FACING WEST.