Isauro Aguirre is suspected of torturing and murdering Gabriel Fernandez, who was the child of Aguirre's girlfriend, Pearl Fernandez. Fernandez is also accused of torturing and murdering her child and will be tried separately.
Detective Elliot Uribe testified that he interviewed Aguirre three times on May 23, 2013, only hours after Gabriel was found unresponsive at his Palmdale apartment.
Uribe said that in the beginning of the interviews, Aguirre was lying. But as the interviews progressed, Aguirre became more truthful.
During the first interview, Aguirre described his relationship with all of Pearl's children as "good." He also said he did not call them his step children, he simply called them his kids. Aguirre also told Uribe that he would come home from work around 6 or 7 p.m. and often Pearl would tell him how the kids had behaved.
Aguirre told the detective that Gabriel was "difficult" and that the boy had lived with Pearl's parents for some time.
This interview was also conducted hours after Gabriel had been rushed to the hospital. Uribe asked Aguirre what happened that led to the child's hospitalization.
In the recordings, Aguirre described how Gabriel made him mad and said the 8-year-old at one point told his mother that she should leave Aguirre. He said that is when he lost control and admitted to hitting Gabriel harder than he'd ever hit anyone.
"Maybe 10 times," he said.
At one point, Aguirre admitted he lost count of how many times he hit the child.
In cross examination, the defense played a video recording of Aguirre's interview with detectives. Here, Aguirre described trying to revive Gabriel when he stopped breathing.
"When I took him out, I could hear bubbles, or air bubbles, so I told her to get me the phone so I can call 911. She did. So I had them on speaker and they were helping me to do compressions, you know, CPR," he said.
But the prosecution fought back in their redirect, asking Uribe if he thought Aguirre was telling the truth during those interviews.
"No," Uribe said.
The trial will resume Thursday morning.