PITTSBURGH — Asked about the mental state of Bradley Demitras, the Pine Township truck driver whose 6,000-pound wood chipper struck and killed two toddlers and their father last month, Allegheny County District Attorney Steven Zappala said he didn't really care.

"I am more concerned with the impact on Mrs. Morrison than him," Zappala said flatly. "As a D.A. you should be objective, but Mr. Morrison did nothing wrong. He was proceeding lawfully down that highway, and in a few seconds he was dead."

Zappala spoke at a news conference Thursday about the accident and the arrest of the truck's driver.

Demitras, 34, of Pine Township, Allegheny County, turned himself in to police Thursday morning, a day after police charged him with 13 criminal counts, including vehicular homicide and involuntary manslaughter for each of the three victims.

He is being held in the Allegheny County Jail without bail. His preliminary hearing is set for 8:30 a.m. next Friday at the Municipal Courts Building in Pittsburgh.

Killed in the violent accident on Route 8 in Richland Township were Cranberry Township residents Spencer Morrison, 37, and two of his triplets, Garret and Alaina Morrison, 4. The third triplet, Ethan, remains at Children's Hospital in critical but stable condition with head, facial and leg wounds.

Nicole Morrison, the wife and mother of the victims, was not in the Honda Odyssey minivan that was crushed in the incident.

Demitras was driving a dump truck that was pulling the 6,050-pound industrial wood chipper owned by his employer, O'Connor Tree Service of Middlesex Township.

Investigators have discovered that the chipper was improperly connected to the truck and that Demitras took two Percocet pills the morning of the crash and drank beer about an hour before the chipper flew off the northbound truck and slammed into the southbound Morrison van.

In a statement to police, Demitras also admitted to having consumed a half bottle of bourbon and an illegally obtained OxyContin tablet the night before the accident. He also stated that he had a hangover the morning of the accident.

Demitras further admitted in the statement that he had failed to check the connection between the truck and the chipper trailer before he parked them in a bar parking lot the morning of the accident.

He said he then left in another truck for a job site and later returned to take the truck and chipper back to the tree company's lot in Middlesex Township. He told police that he again did not check the connection between the truck and trailer before leaving the bar parking lot.

The police also said in an affidavit that they found the truck with the inspection sticker that belonged to another truck owned by the tree service.

Police further said that their investigation showed that the truck Demitras had been driving had a number of safety violations. They said the violations would not have contributed to the accident, but would have kept the truck off the road.

Police said an individual who had inspected the truck in January told them that it had failed a safety inspection and did not get an inspection certificate.

After being charged Thursday morning, Demitras was led out of Allegheny County police headquarters in Pittsburgh in handcuffs about 10:30 a.m. Although reporters asked him if he felt at all sorry or if he had anything to say to Mrs. Morrison, Demitras kept his head down and silently entered the rear of the Northern Regional Police cruiser to be taken to his arraignment in downtown Pittsburgh.

Minutes earlier, Demitras' attorney Michael Moser told reporters his client is "distraught" over the events that lead to the Morrisons' deaths, and that he continues to cooperate with investigators.

"He is an honest, decent person involved in this horrible situation," Moser said. "The (Morrison) family is in his thoughts and prayers."

Zappala said the vehicular homicide and involuntary manslaughter charges could each carry a 3- to 12-month sentence, with the possibility of nine months of additional time being added by a judge because of the age of the children killed in the crash.

Zappala said 11 search warrants have been issued so far in the investigation, and more are forthcoming. He said if the investigation into O'Connor Tree Service turns up any evidence that shows the business may have contributed to the deaths, the business would be shut down.

"I've shut down businesses before," Zappala said.

Zappala said the forged documents charge against Demitras stems from the investigators' discovery that phony inspection stickers were transferred from another O'Connor truck to the one involved in the crash.

Zappala said toxicology testing performed on Demitras at the time of the accident revealed the presence of opiates in his system. Northern Regional Police Chief Robert Amman said the chipper's connection to the ball on the truck was only resting there, with neither locking pin engaged. He said the safety chains designed to prevent the chipper from detaching from the truck were not attached, and there was no electronic braking or lighting connection between the truck and the chipper.

Zappala said no inspection or registration laws exist for equipment being hauled behind a truck, but the Morrison accident may spawn just such laws.

"You are going to see changes," said Zappala. "You lost three lives."

He said motorists traveling alongside such vehicles should observe the connections between a truck and the piece of equipment or trailer it is hauling

"If these chains aren't hooked, call 911," said Zappala.

Amman said investigators have 10 eyewitnesses who saw the chipper hit the Morrison van. He said those witnesses told him the chipper began weaving wildly, then bounced back and forth before detaching and smashing into the van. Zappala said the chipper, traveling at 70 mph, might have been airborne when it hit the Honda Odyssey. He said the damage to the van was so extensive that certain accident investigation tests could not be performed on it.

He said the skid mark from the chipper measured 165 feet. He said after the impact, Demitras turned around and came back to the scene. He said Demitras was properly licensed to operate a commercial vehicle.