Jennifer Bigham was deemed insane after she drowned her 3-year-old daughter in a bathtub. Now, three years later, she is able to walk free from jail after doctors determined she had regained her sanity.

Bigham, of Modesto, California, admitted to killing her daughter in 2010, but she was found not guilty of murder by reason of insanity.

She was released from jail Tuesday after doctors declared her sane.

There were two relatives home when Bigham drowned her daughter. They heard the girl splash and scream, but by the time they got to the bathroom she was unconscious and Bigham had stabbed herself and locked herself in the bedroom.

The ruling is rare, however, as the judge decided not to send her to a psychiatric hospital but sent her to jail instead.

While there is much controversy around her release, School of Law Professor John Meyers said people have to understand that she was proven not guilty by reason of insanity.

"A verdict of not guilty by reason of insanity means not guilty," Meyers said.

"It may seem anomalous to people that a person who murders a child could go 'free' after three years, but what people need to remember is that if it's a verdict of not guilty by reason of insanity, don't forget the not guilty part."

Prosecutors, however, think she should still be in jail.

"She's a danger to society," said Elaine Casillas, a deputy district attorney. "She's not been evaluated properly."

They plan to appeal the decision.