'We seek neither mercy nor sympathy,' Ira Sorkin, lawyer for Bernard Madoff's (left), wrote to a federal judge. Bernard Madoff's lawyer yesterday asked for leniency from the judge who will sentence the convicted swindler on Monday, appealing to him for a prison term of 12 years, rather than the 150-year maximum he could receive under the law. In seeking the lighter sentence, Madoff's lawyer, Ira Sorkin, cited his client's cooperation with law enforcement - but also the state of mind of Madoff's victims. In a letter delivered to federal court in Manhattan, Sorkin urged Judge Denny Chin to resist the 'mob vengeance' he said is being advocated by scores of angry victims beseeching the court to punish Madoff as harshly as possible. 'We seek neither mercy nor sympathy,' Sorkin wrote. 'Respectfully, we seek the justice and objectivity that have been - and we hope always will be - the bedrock of our criminal justice system.' Madoff, 71, confessed in December to defrauding his customers of at least $50 billion over decades by failing to invest their money. Instead, he paid hundreds of millions of dollars to himself and his family, to select investors, and to brokers who brought him business. With ordinary investors, he paid off one with another's money, until the scheme collapsed. He pleaded guilty in March to 11 counts of fraud, perjury, and money laundering. Sorkin said Madoff will speak at the sentencing, 'to the shame he has felt and to the pain he has caused.' For scores of Madoff's victims, no punishment is great enough for the man who stole their life savings. Prosecutors submitted letters from 113 of them to the court last week, recounting what even Sorkin acknowledged were 'heart-wrenching stories of loss and deprivation.' Two siblings writing on behalf of their mother, Florette Silver, a retired New York City schoolteacher, said the losses Madoff had inflicted on her caused 'incredible anxiety, devastating financial impact and broken dreams of secure old age.' They urged the judge to give Madoff the maximum sentence. Other letters are filled with references to Madoff as evil and a devil, one writer going so far as to call him a 'vicious animal' whom he hopes 'suffers for the next 30 years.' Sorkin said he was not disputing the severity of Madoff's crimes. But he complained about death threats and anti-Semitic e-mails directed at him and at Madoff. It is the duty of the court, he said, 'to set aside the emotion and hysteria attendant to this case and render a sentence that is just and proportionate to the conduct at issue.' Based on his age, Madoff has a life expectancy of another 13 years, Sorkin argued, so a prison term of 12 years would have the effect of a life sentence. A 15- to 20-year term would achieve that goal without 'disproportionately punishing' his client, Sorkin added. And he cited examples of Madoff's cooperation as reason for leniency. Beth Healy can be reached at bhealy@globe.com. NOT SEEKING SYMPATHY 