WHITE PLAINS, N.Y. (CBSNewYork/AP) —  In a measure of mercy for a convicted mother-turned-murderer, a judge in White Plains on Wednesday sentenced Lacey Spears to less than the maximum for poisoning her own 5-year-old son with <a href=”http://newyork.cbslocal.com/2014/06/17/lacey-spears-pleads-not-guilty-to-poisoning-5-year-old-son-to-death-in-westchester-county/”a lethal dose of salt.

As CBS2’s Lou Young reported, Spears we sentenced to 20 years to life in prison, as the judge said he hoped she would get help behind bars.

Spears, 27 – most recently of Scottsville, Kentucky – offered no explanation or apology before being sentenced in the death of her bright-eyed, blond-haired son, Garnett-Paul Thompson Spears, in Westchester County.

Spears listened in obvious discomfort as first the assistant district attorney, and then the judge, recapped her crime of poisoning Garnett with salt using a feeding tube that should have been removed years ago.

They said Spears kept her son sick in a world of doctors and hospitals – and obviously killed him – to harvest sympathy in “mommy blogs” and online posts.

“Garnett Spears should be in school today and he’s not because his mother murdered him,” Assistant Westchester County District Attorney Doreen Lloyd said at sentencing.

“He had a right to grow up, and a right to grow old,” Lloyd added. “And she stole that from him.”

Spears turned away for much of the sentencing hearing, her hands cuffed behind her back throughout.

“Your honor,” Lloyd said to Westchester Supreme Court Justice Robert Neary, “her actions were beyond depraved, despicable and evil.”

When Spears turned her back in the courtroom, CBS2’s Young could see her face clearly from the gallery. At times, she was crying, her bottom lip quivering. Other times, she looked up at her attorney with an incredulous expression on her face as if to say, “I didn’t do it.”

“How could a mother treat her innocent child in such a callous, inhumane and calculating manner?” Neary said.

When asked by the judge whether she she’d like to say anything before sentencing, Spears replied, “No sir.” She displayed no emotion at the moment of sentencing.

The state had asked for the maximum penalty, the defense for the minimum. The judge split the difference, mentioning for the first time the mental illness at the heart of the horror.

“One does not have to be a psychologist to realize that you suffer from a mental illness known as Munchausen by proxy. I hope you, over the next few years, come to grips with your condition,” Judge Neary said to Spears. “By not imposing the maximum sentence, I’m combining your punishment with something that you really did not exhibit toward your son, namely mercy.”

Munchausen by proxy is a disorder in which, in some cases, caretakers purposely but secretly harm children and then enjoy the attention and sympathy they receive.

The sentence of 20 years to live is five years less than the maximum and five more than the minimum.

Prosecutors said Spears fed her son large amounts of salt through the gastrointestinal feeding tube, causing brain swelling, seizures and death. They believe she administered the salt at their home in Rockland County, as well as in his room at Nyack Hospital in Nyack after he was admitted for seizures. He died Jan. 23, 2014, after being transferred to Westchester County Medical Center in Valhalla.

The boy had a special feeding tube in his abdomen that was left over from an illness he had in infancy, which provided Spears with the ability to sicken her son at their home in Chestnut Ridge and then fatally poison him during subsequent hospital stays, prosecutors said.

Prosecutors alleged Spears purposely sickened the boy to gain attention on social media and called her “a calculated child killer.” Her actions were “nothing short of torture,” one prosecutor said. “The motive is bizarre, the motive is scary, but it exists.”

The defense tried to blame the hospital, saying the boy was dehydrated while in its care. One defense lawyer said there was “no direct evidence” of a crime.

Spears did not testify at the trial.

Following the sentencing, Spears’ attorneys balked at the mention of mental illness and immediately filed an appeal after the sentencing, CBS2’s Young reported.

“We’re not pleased, certainly in light of the fact that we asked for the minimum sentence and certainly in light of the fact that Lacey maintains her innocence,” defense attorney David Sachs said.

Defense lawyer Stephen Riebling said it was odd for the judge to bring the disorder up because Spears “hasn’t been diagnosed with any mental illness.”

Spears, an Alabama native, was living with her son in Chestnut Ridge, New York, when he died. She moved to Kentucky afterward and was living there when she was arrested.

“Throughout his short life, Garnett Spears was forced to suffer through repeated hospitalizations, unneeded surgical procedures and ultimately poisoning with salt, all at the hands of the one person who should have been his ultimate protector: his mother,” Westchester County District Attorney Janet DiFiore said in a statement. “Using the child’s ‘illnesses’ to self-aggrandize herself, Lacey Spears’ actions directly lead to her son’s tortured death.”

Spears could be eligible for parole in 19 years, getting credit for the one year she’s already served behind bars.

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