Jefferson Siegel/NY Daily News via Getty Images
Thomas Gilbert Jr., the Princeton graduate who killed his father after his allowance was decreased, was sentenced to at least 30 years in prison for the crime.
A jury rejected an insanity defense as a judge in the Manhattan court handed down a sentence of life in prison with a possibility of parole after 30 years, which the New York Times noted is the maximum penalty allowed under the law.
Shelley Gilbert asked the judge for "as light a sentence as possible" so her son could receive treatment for a variety of his mental health struggles.
However, the judge rejected Gilberts' insanity defense, telling him that he "knew exactly what you were doing."
Thomas Gilbert Jr., the Princeton graduate who killed his father over a decrease in his allowance, was sentenced to at least 30 years in prison for the crime, according to multiple reports.
A jury rejected an insanity defense put forth by Gilbert and his family as a judge in the Manhattan court handed down a sentence of life in prison with a possibility of parole after 30 years, which the New York Times noted is the maximum penalty allowed under the law.
Gilbert was sentenced on September 27, nearly three months after he was convicted in Manhattan, and was ultimately found guilty of murder in the second degree and two counts of criminal weapon possession.
The then-29-year-old hedge-fund heir shot his 70-year-old father in the head in 2015 after being cut off from most of his $1,000 weekly allowance. Throughout weeks of trial proceedings, prosecutors insisted the murder followed a petty dispute over Gilbert's allowance.
A former girlfriend told the court before Gilbert was convicted that she recalled the heir becoming "scared" and "upset" when he discovered his father would reduce his allowance to just $300 per week.
"He was concerned about getting cut off financially," Ressner said, the New York Times reported in June.
However, Gilbert's mother repeatedly insisted that her son was at an unprecedented low in mental illness when he shot his father, and asked the judge ahead of the sentencing for a lenient timeline.
CNN reported that Shelley Gilbert said that she wanted her son "to be given as light a sentence as possible."
"As I've said many times in court, we've been trying to get Tommy into a hospital for 15 years," she reportedly said. "He's too sick to be able to judge. He needs to be in a hospital, had he been so my husband would still be alive."
However, the Times reported that Justice Melissa Jackson rejected the characterization, telling Gilbert that he "knew exactly what you were doing."
"You were not insane at the time you killed your father," she said, according to the Times. "You were not insane then. You are not insane now."
Throughout the trial, Gilbert's lawyers painted the picture of a troubled person who had been diagnosed with severe compulsive disorder, depressive disorder, paranoid disorder, and psychosis.
His lifelong place among New York high society also came into play during the proceedings, as emails and internet records depict his mental health and financial status crumbling amid a paid-for Manhattan apartment and memberships at exclusive health and social clubs.
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