Cecil Conner is accused of driving drunk after the child's mother was arrested by a police officer who gave Conner the keys to her car even though he had been drinking.
Five-year-old Michael Langford died when Conner lost control of the car and slammed into a tree.
Thursday, the child's mother testified for the defense that she warned the arresting officer that Conner had been drinking. On Wednesday, she testified for the prosecution.
Under cross-examination, Kathie LaFond testified that she filed a civil lawsuit just 48 hours after the vehicle crash that killed her son. She denied, however, that she's motivated by money, saying Thursday on the stand that she's only seeking justice for her son.
LaFond testified that her boyfriend, Conner, was visibly drunk and her car smelled of alcohol.
LaFond said she told Chicago Heights Police Officer Chris Felicetti at least three times that she was Conner's designated driver before Felicetti arrested her for a suspended license and ordered Conner to take the wheel.
Forty minutes later, Conner crashed the vehicle, killing LaFond's 5-year-old son who was riding in the back seat.
Conner's blood-alcohol level was more than three times the legal limit.
"Cecil Conner should be held accountable for his actions, and he should be required to serve the time for the laws that he broke on that night," said Kim Lozano, cousin of victim's father.
LaFond testified she was handcuffed, placed in Felicetti's squad car and taken to the police station, where she signed impound forms even though her vehicle was not impounded.
The defense contends LaFond was arrested, and Conner instructed to drive, because police wanted to collect the $500 impound fee.
Thursday, relatives of the dead boy's father said they blame Conner, Officer Felicetti and LaFond for the child's death.
"We do not believe for one moment that the police officer was made aware of the fact that Cecil Conner had been drinking, because there is no way that any police officer would hand the keys over to somebody they knew was under the influence of alcohol," Lozano said.
Earlier, the jury heard testimony from defense witness Jennifer Tartt, the fiancee of Cecil Conner's cousin.
Tartt testified Conner had been drinking at her apartment and was "completely wasted," stumbling, slurring his speech, and smelling of alcohol before LaFond picked him up.
Tartt also testified Conner called her before the crash, while he was driving, fearful because he was drunk. But, before he could tell her his location so she could pick him up, the phone cut off.
Defense attorneys called Officer Felicetti to the stand and he denied that Conner or LaFond informed him that Conner was drunk.
Thursday morning, prosecutors wrapped up their case by including testimony from an accident reconstruction expert. He said that Conner had been traveling at around 70 mph, more than twice the posted speed limit.