Madoff Plea Makes No Sense

Thursday, Bernard Madoff pleaded guilty and allocated to a $65 billion ponzi scheme that he had been running for decades. The plea makes him legally guilty of eleven counts including fraud, perjury and money laundering. He will be sentenced June 16th, and could receive as long as 150 years in jail. Given his age of 70, even if the judge goes easy on him it will surely amount to a life sentence. Given the situation, why would he plead guilty? What's the upside to him for doing so?