ARDMORE, Okla. (CBSDFW.COM) – Federal officials are trying to get medical records of and interview the North Texas truck driver in the middle of a deadly crash investigation. Investigators obtained and delivered subpoenas for the medical records Russell Staley, of Saginaw.

CBS 11 News has received updated information on the Oklahoma crash that killed four Texas college softball players on Friday night.

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Meagan Richardson of Wylie, Brooke Deckard of Blue Ridge, and Fannin County residents Jaiden Pelton and Katelynn Woodlee were all killed.

All of the girls were on the North Central Texas College team bus, when an 18-wheeler slammed into them. NCTC is located in Gainesville, about 70 miles north of Dallas.

The NCTC girl’s softball coach was driving the bus, with 15 players on-board, when the crash happened.

As they conduct their safety investigation, officials with the National Transportation Safety Board (NTSB) say they want the records of 53-year-old Russell Staley, because there can only be three potential causes for the crash, that happened in Davis, Oklahoma, about 60 miles north of Gainesville:

  • vehicle problem
  • road and environmental (like weather)
  • or driver was impaired

Staley reportedly told investigators that he had been distracted by something in his cabin before the accident. The NTSB has seven teams of investigators working at the crash scene.

NTSB investigator Kristin Poland takes laser scans of the 18-wheeler involved in the Davis, Okla., bus collision that left 4 members of the NCTC softball team dead. (credit: NTSB)

NTSB investigator Kristin Poland takes laser scans of the 18-wheeler involved in the Davis, Okla., bus collision that left 4 members of the NCTC softball team dead. (credit: NTSB)

On Monday we learned the truck traveled about 950 feet after it left its lane and crossed the median. NTSB officials say the semi was traveling at about 70 mph – the posted speed limit at the time. Investigators say the truck driver never tried to stop and in fact the semi continued for another 300 feet, crossing the southbound lanes and barreling through and uprooting trees, before coming to a stop.

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Part of the safety investigation is looking at whether median barriers should be installed on the stretch of Interstate-35. But it could be several weeks, or even months, before the Oklahoma Highway Patrol completes their law enforcement investigation and the NTSB completes their safety investigation.

“We’re very interested in this accident. We want to make sure that those four lives were not lost in vain,” NTSB board member Robert Sumwalt said during an afternoon press conference. “So not only will we look at this particular accident moving forward, but we will want to use this accident as a lesson that we can go out and advocate for our recommendations to be implemented.”

Oklahoma Highway Patrol officials say they want to look at driver Russell Staley’s logs to see how long he was on the road before the crash.

While inattention could be a factor, investigators are not saying if that the cause.

(©2014 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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