Anthony Chambers wrote in a legal filing that spending the rest of his life in prison amounts to cruel and unusual punishment for 25-year-old Umar Farouk Adbulmutallab, The Detroit News reported Tuesday.
"It is fair to say that the mandatory minimum sentence of life is excessive and grossly disproportionate to the conduct," said Chambers.
Abdulmutallab pleaded guilty in October to trying to use a bomb in his underwear to blow up Northwest Airlines Flight 253 as it approached Detroit's Metro Airport on Christmas Day.
He acted as his own lawyer at his trial and complained that attorneys appointed to help him lied and misled him.
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