A 12-year-old Fort Washington boy could be jailed until he is 21, after he was convicted of involuntary manslaughter in juvenile court Wednesday, The Washington Post reported.

After a two-day hearing, a circuit court judge convicted the preteen for the fatal beating of his foster sister, two-year-old Aniyah Batchelor in July, according to reports.

The boy pleaded guilty to the lesser charge in court, after Prince George's County Police initially charged him with second-degree murder in July, in addition to other charges. According to The Gazette, the boy took the Alford plea which means the "juvenile is not admitting to the criminal act, but acknowledges that prosecutors could find him guilty on his most serious offense of second-degree murder" if it went to trial.

Circuit Court Judge Sherrie L. Krauser asked the boy if he understood the plea, but according to The Washington Post, he wasn't sure what it meant. Krauser then went onto explain the plea, noting that the boy's lawyers will not be able to call witneses or object to any evidence in the case, The Gazette reported.

According to Prince George's County Police, the boy's father found Aniyah unresponsive, after he was called home by his 15-year-old daughter on July 3.

The toddler, the boy and another four-year-old girl were in the care of the 15-year-old girl at the time of the beating, police said. Aniyah was placed in the family's care after she was removed from her mother's home for alleged abuse.

An autopsy performed on July 4 confirmed that Batchelor was killed by blunt force trauma and police found that the 12-year-old had beaten the toddler repeatedly, according to the PGPD blog.

In court Wednesday, Prince George’s Assistant State’s Attorney Wesley Adams said that an autopsy report revealed that the toddler had external signs of abuse including 53 bruises on her body, 14 bruises on her head and she also suffered internal injuries, The Gazette reported. Adams also said in court the boy admitted to punching Aniyah six times in the stomach, The Washington Times noted.

The last time a preteen was charged with murder in Prince George's County was in 2006, PGPD Spokeswoman Julie Parker said in July. In Maryland, in order to be charged as an adult a juvenile must be 14; however, in special cases, this law can be waived.

According to The Washington Post, although the boy could be jailed until he is 21, he'll first undergo a medical evaluation. He will stay in the Cheltenham Youth Facility until Oct. 23 for a disposition hearing.

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