"I killed that girl, I killed her ---damn it," Plumer is heard saying on the videotape.
Another trooper at the scene, Eric Burnett, was heard saying to Plumer, "You did your job."
Under questioning Tuesday about his actions, Plumer said he was frustrated about the chase.
Despite pursuing a suspect's car at speeds of up to 107 mph, becoming involved in an accident with the vehicle at the intersection of U.S. 11 and W.Va. 45 near Martinsburg, and setting up a roadblock, police were unable to get the Nissan 200 SX stopped until it plowed into the rear of Smailes' Ford Escort near Smiley's Inn, Plumer testified.
During the 15- to 20-minute videotape of the chase, Plumer is heard saying "die mother-----."
"This was a very intense pursuit. I'm human. We all say things we don't mean," Plumer told Berkeley County Prosecutor Pamela Games-Neely.
Sparkman, 28, the driver of the Nissan, was taken to Winchester Medical Center for head injuries. The Gerrardstown man later was charged with driving under the influence resulting in death, a felony that carries a punishment of up to 10 years in jail.
Defense attorney Aaron Amore said the state police acted recklessly, and that the 12-mile chase was bound to end tragically.
Smailes' car was forced off the road into a utility pole, and the videotape showed Sparkman face down along the road.
"Somebody was going to die, whether it was him or Amanda Smailes," said Amore.
The footage was filmed by two cameramen for "Real Stories of the Highway Patrol," a television program about actual situations police face on their daily patrols.
The footage of the pursuit was never aired.
Smailes' parents, John and Cynthia Smailes, left the courtroom before the tape was played.
Circuit Judge David Sanders had recommended that anyone who felt the videotape would be too upsetting should wait outside the courtroom.
Smailes' mother, Cynthia, became visibly upset earlier when officials testified that Amanda Smailes died from blunt force trauma.
The film showed the night chase winding through other traffic on the road. The suspect's car was being driven erratically, and Plumer radioed ahead that he was following a motorist who was "driving like a nut."
The pursuit started about 1 a.m. on U.S. 11 near Musselman High School, when Plumer saw a car swerve off the shoulder of the road, police said. The chase continued toward Martinsburg to the intersection of W.Va. 9, W.Va. 45 and U.S. 11, where the Nissan spun around in the intersection and collided with Plumer's cruiser.
The chase continued south on U.S. 11 and ended moments later with the collision.
The chase was one of two that state police were involved in that evening, according to testimony.
Roger Lee Smith testified that he and Sparkman were driving to a bar near Martinsburg earlier in the evening when they saw a trooper coming down U.S. 11.
Sparkman, who was driving, "took off," driving between 80 mph and 100 mph, Smith testified. Police turned on their sirens, but Sparkman continued driving north on the highway toward Martinsburg, Smith testified.
"He told me to be quiet," said Smith, referring to Sparkman.
Sparkman "did a donut" at the intersection of U.S. 11 and Tabler Station Road and headed south on the highway, finally outdistancing the police, according to Smith.
Smith testified he and Sparkman had been drinking before the incident at a relative's house and at a bar.