CHICAGO (CBS) — A state child welfare worker who investigated an abuse claim months before a 5-year-old suburban Chicago boy was found beaten to death has defended his record.

Carlos Acosta and a supervisor were fired from the Illinois Department of Children and Family Services after a lengthy disciplinary process. Both were involved in an investigation of Andrew “A.J.” Freund, who was found dead in April and had a extensive contact with the child welfare agency. The boy’s mother, Joann Cunningham, pleaded guilty to murder and his father, Andrew Freund, is awaiting trial.

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(Davenport Funeral Home)

Acosta was the child protection specialist assigned to check a December 2018 call from Crystal Lake police about a bruise on Freund’s right hip. The boy gave varying explanations for the injury, including that the family dog had done it during play. But records show he also told an emergency room doctor, “Maybe mommy didn’t mean to hurt me.”

Acosta, who is also the subject of a federal lawsuit stemming from the case, said department policy is that children’s statements become less reliable each time they are interviewed. He said he followed protocol in not going back to question the child about the bruise and that the child’s injuries didn’t meet the threshold to get a second opinion from a pediatric specialist.

Acosta said he’s emotionally torn but stands by his decisions.

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“I don’t deny the fact that I was there four months before and that’s something that I’m going to have to live with forever,” Acosta told Shaw Media Illinois. “And again, should have, could have, would have. Did I still follow the policy and weigh the evidence that I had at the time? Yes.”

JoAnn Cunningham and Andrew Freund Sr. have been charged with murder in the death of their son, 5-year-old A.J. Freund, whose body was found buried in a shallow grave seven miles from their home in Crystal Lake. (Source: McHenry County Jail)

Acosta is also a McHenry County Board member. His former supervisor, Andrew Polovin, was also removed from the state Department of Children and Family Services. He has not spoken publicly about the case.

Authorities found AJ Freund buried in a shallow grave in a rural area in April, about a week after his parents reported him missing from their Crystal Lake home.

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