Vest pleaded guilty to aggravated robbery and received an eight-year prison sentence. Part of his plea bargain was that he would testify against Johnson.
Johnson was indicted for murder before a McLennan County grand jury on 29 November 1996.
Vest testified that at the service station, he had exited the car from the passenger’s side and begun filling the car with petrol. Wetterman had come out to assist and had begun talking to Vest. Johnson had then exited the car from the driver’s side and had walked to the back of the vehicle. Vest had asked him if he had the gun on him, to which Johnson had responded by lifting his shirt to display the pistol tucked into his trousers. As Vest had replaced the petrol pump, he heard a shot and had looked around to see Wetterman falling to the ground. Vest and Johnson had hurried into the car and sped away.
Another friend testified that Johnson had bragged about the incident in the following days. He said Johnson had admitted to the shooting, saying he shot Wetterman in the face after he thought he heard Vest say “Shoot’’. Other friends testified that Johnson made fun of Vest for crying after the incident.
Johnson initially tried to say that he had an alibi and was at home on the day of the murder but after his arrest he admitted to a psychologist that he had been present at the time of the killing. Physical evidence also placed him at the scene, in the form of DNA collected from hairs and cigarette ends found in the Cadillac.
At trial, Johnson did not testify in his own defence but later told reporters that Vest had murdered Wetterman. Johnson maintained that he had been driving but had remained in the car while Vest got out to fill the car with petrol. Johnson said he did not even see Wetterman. He claimed that Vest shot the attendant and then yelling, “Go, go, go!” jumped back into the car.
Whilst Johnson had no previous convictions, several witnesses described violent incidents in his past. His former girlfriend said he that he had beaten her after accusing her of ‘sleeping around’. Other friends testified that Johnson had attacked a man with a knife; aimed a gun at a neighbour during a confrontation; attempted to run a man over and had once run over a cat and then reversed over it to ensure that it was dead. A man testified that Johnson had responded, “So what?” when told the victim in his murder trial was married.
On 6 May 1997, Johnson was found guilty of murder. Two days later he was sentenced to death by lethal injection. As the verdict was read out, he turned and screamed obscenities at the Wetterman family.