Officials said an argument over the sale of a car led Pryor to get into an altercation with another driver, which ended when he allegedly crashed into Livingston's bike and fled the scene.
During the court hearing Thursday, officials said Pryor had just purchased a vehicle another man wanted. That other man ran into Pryor minutes earlier and confronted him about it. Pryor started driving down the street, bumping his van into the other man's vehicle over and over until he eventually lost control and hit Livingston.
"It's useless. Someone lost their life over two idiots," said Edward Ziemba, Livingston's uncle, who was in the courtroom on Thursday.
Ziemba said he thinks the driver of the other van should also be held accountable.
"I was handling this really well until I saw the video and I see these people walking nonchalantly out of their van, no compassion about my nephew who is laying on the ground dying, and they don't care," said Edward Ziemba, victim's uncle.
Surveillance video captured part of the accident that led to Livingston's death. It shows the van crashing through a wrought iron fence and hitting a nearby building. Moments later, two men jump out followed by a woman and child. Police say this was the van that Pryor had been following, ramming into it over and over until he lost control, and hit Livingston's bike.
Detectives at Area 5 would not saw whether they will arrest the driver of the other van, who may have started the altercation. The investigation is ongoing.
"Our detectives followed this aggressively. We situated pool videos, looked at what we had. Detectives did a good job, but this never should have happened. That's the sad part. It never should have happened," said Supt. Jody Weis, Chicago Police Dept.
Pryor's family was also in court Thursday. Though they would not speak on camera, they told ABC7 their hearts go out to Livingston's family. They said that while they recognize his guilt, they feel that a first-degree murder charge is excessive.
In court, Pryor's defense attorney raised the question, saying she doubts the prosecution can meet the criteria for such a charge. Bond was set at $2 million .