MARKHAM, Ill. (WLS) -- Testimony began Tuesday at the trial of a man accused of killing a Metra police officer Thomas Cook in 2006. He was the first Metra police officer killed in the line of duty.
Prosecutors' case relies heavily on witnesses wearing wires and a plea deal with a felon who faces life in prison.
Cook was on duty in Harvey when he was shot and killed. His relatives have waited nine years for a trial.
"It feels good to finally start it after so many years of waiting," Pam Cook says.
In September 2006 Pam Cook got a late night visit by three police officers to tell her her husband had been shot and killed while on duty.
"He was a loving father. He did everything with us," Cook says.
"The support she's gotten is unbelievable," says Terri Hillard, Cook's sister in law. "I don't think she could get through without the support she's gotten. And we just hope at the end of this she can put closure to this, and that the people that committed these crimes will serve their time."
Cook was a Metra police officer working a special assignment after armed robberies at a Harvey Metra station. Jemetric Nicholson was charged in 2010.
A prosecutor in opening statements said of Officer Cook, "He was targeted in his vehicle, in that marked squad, because that defendant needed money and needed a gun."
Defense attorneys referred to a plea agreement with one of witnesses for the prosecution saying, "They do have to have their deals, but it doesn't mean they are telling the truth."
Nicholson's relatives say they feel for the Cook, but the prosecution has the wrong person.
"It was not him. And I pray they caught the person that done that," says Nicholson's fiance, Samaria Matthews.
"I just hope my little brother is found not guilty, because he's not guilty of this case. He didn't kill no Metra police officer. He didn't kill nobody," says Lazeric Lipscomb, Nicholson's brother.
The last witness called Tuesday was Jeremy Lloyd, who has already pleaded guilty to this murder as well as the attempted murder of a Harvey police officer. Lloyd admitted he entered plea deal and testified that he saw Nicholson hold up a gun, but didn't see him pull the trigger.
There was also testimony from the chief of the task force acknowledging that there were other suspects at the time, and that there is no physical evidence linking Nicholson to the scene. The trial continues and could go in to next week.
Trial begins for man accused of Metra cop's 2006 murder