Ruth Dirienzo-Whitehead, 51, has been convicted of killing her 11-year-old son before driving to a Jersey Shore beach where investigators said she drove her vehicle in the ocean in April of last year.
In delivering the guilty verdict on Thursday morning, a judge in a Montgomery County courtroom refused to find mental illness as a defense.
In hearings this week, Dirienzo-Whitehead's defense argued that she strangled her son, Matthew Whitehead, to death with a belt on April 10 in a bedroom of their Horsham Township home because she was having a psychotic break and felt she was sparing her son a painful life.
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After the killing, Dirienzo-Whitehead drove Cape May, where officials found her vehicle partially submerged in the ocean just off of Beach Avenue in Cape May, New Jersey.
Dirienzo-Whitehead was later found walking in Wildwood Crest, New Jersey, shortly after and taken into custody.
A defense expert testified that Dirienzo-Whitehead suffered from depression and mental illness at the time of the killing.
And, her lawyer told NBC10 that she felt her world was crashing in on her, financial pressures and her son's awareness of them had become too much for the Horsham mom.
However, prosecutors argued that the killing was premeditated, revealing that she had numerous Google searches on how to strangle someone and she had done research on mental illnesses that lead moms to kill their own kids.
Also, family owned a beach house in Wildwood Crest, NJ, which they put up for sale just prior to the killing.
The home sold for more than $800,000.
Instead, prosecutors argued that Dirienzo-Whitehead blamed her husband for the family's financial issues and said she was motivated to kill her child by a mix of anger and revenge.
Dirienzo-Whitehead has been convicted of first-degree murder, which carries a mandatory sentence of life in prison.
Her sentencing hearing is scheduled for Friday.
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