Dr. Elizabeth "Beth" Allison is a pediatric oncologist and the killer of con artist Gideon Blake. She killed Blake with rat poison and made sure that he would die at a restaurant they were supposed to meet at.
Allison was tried under the motive that he robbed her with a real estate scam. Instead, it was discovered that she killed him because of his latest con as a spiritual medium, a con that Allison fell for but ultimately found out. She argued that the grief caused by her job coupled with the pain of the revelation drove her over the edge. On the stand, she had a psychotic breakdown and tearfully said that Blake was with the children in Heaven.
The prosecution was sympathetic and agreed for Allison to be institutionalized. (L&O: "Compassion")