They called her "retarded" on the basis of an IQ test administered after her arrest.
One has to wonder about the reliability of an IQ test for somebody who is under indictment for murder, and furthermore under a defense lawyer's care.
People who are genuinely retarded don’t try ot hide the things they do since they don’t see right/wrong the way we do. Therefore they are not culpable. But this woman tried to hide it.