A Colorado former foster mother was found guilty of killing her 16-month-old foster child, who showed signs of long-term abuse. 

A Boulder County jury convicted Cassidy Renee Lemmon, 25, Monday on two counts of child abuse — knowingly/recklessly causing death and one count of child abuse — negligence causing death, following the 2019 killing of foster child Thomas Eugene Boyles, according to Law & Crime, citing authorities.

Lemmon’s then-partner and co-foster parent, 27-year-old Vincent Ray Johnson, was initially charged with the same counts of child abuse. However, the charges were reduced to one count of child abuse – negligence resulting in death in exchange for his testimony against Lemmon, stipulating a lesser prison sentence of 12 years.

“This defendant and her co-defendant extinguished the life of a beautiful little boy. We appreciate the jurors who gave up more than two weeks of their summer, worked through evidence and expert testimony, and reached the right verdict,” District Attorney Michael Dougherty said in a statement to Law & Crime. “From the beginning of this case, the detectives with the Longmont Police Department and our prosecution team were determined to secure justice for Thomas. They did an outstanding job with this very tragic case.”

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The charges stemmed from an incident that took place on April 22, 2019, when officers responded to a 911 call regarding a 1-year-old unconscious and not breathing, according to an affidavit obtained by the Longmont Times-Call and Law & Crime. When authorities arrived on the scene, Lemmon was performing CPR on Boyles’, which was described as “a little deep,” per the affidavit. First responders also noted that the baby had bruising on his face and body. 

Boyles was taken to the Longmont United Hospital and later airlifted to the Children’s Hospital in Aurora, where he was pronounced dead just before 5 p.m. on April 24, 2019.

According to the affidavit, the forensic pathologist determined the boy died from blunt force injuries. Some of the injuries included “intracranial hemorrhage, multiple rib fractures, liver and spleen injuries” as well as a spinal fracture and subdural brain bleed, all of which appeared to be from child abuse. Doctors said Boyles’ fractured ribs were at different stages of healing, which indicated evidence of long-term child abuse. 

In an interview with investigators, the foster parents said that Boyles’ “sensory problems” would cause him to regularly injure himself. They also said that Boyles had been sick for the past couple of weeks and threw up twice before he stopped breathing. Additionally, Johnson argued the broken ribs were from CPR on the child.

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But the forensic pathologist determined, “There is not a sufficient explanation for the severity of the head injuries or healing rib fractures,” according to the affidavit, and ruled his death a homicide.

Text messages between Lemmon and Johnson revealed growing anger toward the child. In one message sent weeks before the death, Lemmon purportedly wrote, “He doesn’t f-cking listen so hes not allowed to do some things. It’s not my fault hes stupid,”

She also allegedly wrote, “I keep him away from doing those stupid things so he’s not in trouble all the time and pissing me off.”

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In a separate message, Lemmon had referred to Boyles as being “worse than the devil,” Law & Crime reported. 

When the foster parents were given medical evidence negating their story, Johnson admitted to police that Lemmon “would hit him and throw him,” when she was frustrated with the child, per the affidavit. 

“After a while, the last couple of times she tossed him, Thomas would just land and sit there with his hands in his lap,” Johnson said, adding that the baby would cry from neglect. 

According to the District Attorney’s Office, Lemmon will next appear in court Oct. 30 to face her sentencing. She faces a total sentence of 16 to 48 years in state prison.