Survivors may be able to explain the circumstances surrounding a crash on New Mexico's Interstate 40. State police know the fatal accident occurred when a tractor-trailer crossed from the eastbound lanes into the path of a rental truck.

All three people in the Enterprise rental died including a 47-year-old father and his 21-year-old son. The 27-year-old rental truck driver was also killed in the fatal accident near Grants. All of the victims were from out of state.

Two people were in the tractor-trailer when the vehicles collided.

State police reported the truck driver's injuries were severe. The man was flown to the University of New Mexico Hospital in Albuquerque. A passenger was treated locally before being transferred to UNMH. The occupants of the semi were not identified.

It's now up to accident investigators to determine what happened before and during the weekday morning fatality. The severity of the truck driver's medical condition could prevent police from getting answers that are critical to the probe.

The tractor-trailer passenger's condition was not reported. A hospital transfer seems to indicate the injuries the passenger suffered were not minor.

Without the benefit of speaking with people in the accident, authorities may depend upon accident reconstruction crews, mechanical and medical tests to understand what caused the fatality.

Some of the concerns will surround the operation of the tractor-trailer. The competence of the driver, the service and accident history of the truck and the policies of a trucking company may all come into play.

Authorities will test to see whether the driver was distracted, fatigued or under the influence of drugs or alcohol. Police mentioned nothing about criminal charges.

The families of those who died in the rental truck and the injury victim in the tractor-trailer may pursue civil court cases. Wrongful death and personal injury damages may be sought against the tractor-trailer driver and possible his employer or truck leasing firm.

Source: abqjournal.com, "UPDATED: Police Release IDs of 3 Killed in I-40 Crash," Jan. 9, 2013