01/23/2013 05:22 pm ET Updated Jan 24, 2013

Jennifer Bigham, 'Insane' Mother Who Drowned Daughter, Released From Jail After Regaining Sanity

A young California mom who was deemed insane when she drowned her daughter is free from jail, because doctors say she's regained her sanity.

Based on the psychiatric evaluation, a judge ordered Jennifer Bigham freed yesterday almost exactly three years after she killed her 3-year-old in a bathtub, according to KOVR.

Two relatives heard the little girl's splashing and screaming, the Modesto Bee reported. By the time they got into the bathroom she was unconscious and Bigham was locked inside a bedroom of the Patterson home with self-inflicted stab wounds.

A beaming smile crossed Bigham's face as she took her first steps as a free woman in a blue, knee-length hospital gown. The 26-year-old can't be tried for murder and child abuse again, because of double jeopardy protections.

The case is considered extremely unusual, experts told CBS, because the judge didn't commit Bigham to a mental hospital after ruling she was not guilty by reason of insanity. Instead, she was jailed.

The doctors that concluded Bigham was insane at the time of the murder in January 2010 were the same ones who testified on Tuesday that she's now a sane person.

Prosecutors disagreed and announced they plan to appeaL the ruling.

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