A truck driver accused of having been under the influence of drugs at the time of a crash was charged in the death of another driver killed by debris from his truck, Butler County authorities said.

Christopher Brumfield, 28, of Franklinton, La., was charged with vehicular homicide and aggravated assault, both while driving under the influence of cocaine, in the Aug. 22 crash that killed Neil Trimble, 26, of Indiana.

"The allegation is that he was under the influence and incapable of safe driving," Assistant Butler County District Attorney Jerry Cassady said. "Our forensic toxicologist backs up that allegation."

Mr. Brumfield had previously faced only traffic citations for the crash, but Butler County prosecutors on Tuesday added the new criminal charges, which carry up to 20 years in prison if the defendant is convicted.

Mr. Trimble was killed when he tried avoid the collision between Mr. Brumfield's truck and a box truck on Route 422 in Clearfield Township. Mr. Brumfield's truck overturned and Mr. Trimble was killed instantly when he was struck by equipment and other items thrown from the truck.

Mr. Brumfield did not have an attorney so a preliminary hearing scheduled for Tuesday was postponed until Oct. 31 so he could apply for a public defender. Brumfield remained in the Butler County Prison, unable to post $75,000 bond.