Accident investigators are looking into what role a truck driver's commute played in the fatal crash that also injured comedian Tracy Morgan.
A spokeswoman for the National Transportation Safety Board says Wal-Mart driver Kevin Roper lives in Georgia, but his job is based in Delaware.
A criminal complaint alleges Roper hadn't slept for more than 24 hours before the accident. Wal-Mart has not explained what Roper's driving route was.
Roper pleaded not guilty Wednesday to charges of death by auto and assault by auto stemming from the crash early Saturday.
The 35-year-old was driving a Wal-Mart truck when he allegedly swerved to avoid slowed traffic and plowed into Morgan's limo. Morgan and two others are in critical but stable condition. Another comedian was killed in the crash.