A month after their son was run off a Pennsylvania highway and shot to death, the parents of Timothy Davison remain desperate for answers and longing to know the 28-year-old's last words to a 911 dispatcher.
Davison, of Poland, Maine, was making the 1,400-mile trip home along Interstate 81 on Jan. 4 after spending the holidays with family members in Orlando, Fla., when the other driver began tailgating him. Davison lost contact with a Maryland 911 dispatcher as he crossed into Pennsylvania, then called back to say he was being shot at, according to police.
"I don’t want to hear my son’s voice -- that's too painful -- but I do want to read that transcript," the dead man's father, Timothy Davison, said. "I’ve got no answers."
Davison was found dead inside his SUV, which was stuck in a snowbank in the median near Antrim Township in southern Pennsylvania.
Investigators said they believe the killer rammed his pickup truck into Davison's silver Mitsubishi Montero SUV, forcing it into a the snow-covered median, where it became stuck. The driver then got out of his vehicle and shot a couple rounds into the car, striking and killing Davison, police said.
Theresa Allocca said her son was a "very experienced driver," who was operating a vehicle that could have reached 140 miles per hour and easily "outrun" the killer's Ford Ranger-style pickup truck. Allocca said Davison had lived in Phoenix, Ariz., at one point and was comfortable driving at a speed of 100 miles per hour if he needed to.
Davison's parents said they have many questions over what led up to the murder and have filed a formal request in Maryland to view a copy of the 911 transcript. So far, neither the transcript nor a recording of the call has been released, with authorities saying it is because the investigation is ongoing.
Among the questions that agonize his parents are: Did Davison drop-back on the highway in order to obtain a better description of the vehicle following him? Or did he decrease his speed while waiting for police to tell him whether to exit the highway as he approached a ramp?
Neither parent is convinced that a shooting hours earlier is unrelated to the one that killed their son. On the night of Friday, Jan. 3, hours before Davison was killed, a roadway shooting involving a pickup truck in Monaghan Township, Pa., 30 miles away, was reported. Police said shortly after Davison's death that there was no evidence indicating the two incidents were connected.
The shootings occurred roughly seven hours apart, and the gunshots involved in the first incident narrowly missed the victim's head.
"They ruled out that the first shooting was related. How is that?" Davison asked. "Without that person in custody, how could they determine that it's not the same person?"
"I think it's too coincidental in such a short period of time to have such similar events," added his mother.
Davison said he believes more than one person was involved in his son's killing, but declined to elaborate further.
Trooper Robert Hicks of the Pennsylvania State Police had no developments to report when contacted Thursday by FoxNews.com. Hicks noted that certain information obtained by authorities cannot be released because it would jeopardize an ongoing investigation.
The younger Timothy Davison worked as a construction foreman and supervisor.
"I lost three people that day. I lost my son, I lost an employee and I lost a friend," his father said. "He was a good kid and I miss him dearly."
Anyone with information about the shooting is urged to contact PA Crime Stoppers at 1-800-4PA-TIPS (800-472-8477).
Cristina Corbin is a Fox News reporter based in New York. Follow her on Twitter @CristinaCorbin.