Bernard Madoff's lawyer has told a judge scheduled to sentence the disgraced financier next week that 12 years in prison would be sufficient punishment for the man who swindled tens of billions of investors' dollars in one of history's biggest frauds. But a woman who says her family was ruined financially by Madoff's thievery said a sentence that short might only work "if he was hung by his toes" the whole time. The 71-year-old Madoff faces up to 150 years in prison after pleading guilty on March 12 to 11 felony counts including securities fraud and perjury. He admitted operating a massive pyramid scheme for decades. Federal sentencing guidelines call for Madoff to receive a life sentence. Madoff attorney Ira Sorkin said in court papers made public Tuesday that his client "will speak to the shame he has felt and to the pain he has caused" when US District Judge Denny Chin sentences him next Monday. "We seek neither mercy nor sympathy," Sorkin wrote. But he urged Chin to "set aside the emotion and hysteria attendant to this case" as he determines the sentence. Sorkin said a sentence of a dozen years in prison would acknowledge Madoff's voluntary surrender, full acceptance of responsibility, meaningful cooperation efforts and the nonviolent nature of his crime. Still, the lawyer added that a prison term of 15 to 20 years would not disproportionately punish Madoff compared to sentences given other white-collar criminals. "Indeed, such a range will appropriately eliminate concerns for disparate treatment among similarly situated nonviolent offenders," he wrote. "If we he was hung by his toes for 12 years then maybe that sentence would be acceptable," said Candace Newlove of Nederland, Colorado. She said her family was financially ruined by Madoff. Newlove, who is selling her home, said she hopes the judge keeps in mind that Madoff "had a huge impact not only on our family but world economics and trust around the world." Richard Roth of Jupiter, Florida, who lost several million dollars with Madoff and has had to put his house up for sale, said he believes in the court system. "The lawyers can ask for anything he wants," he said. "That doesn't mean anything. I'm sure he's going to spend the rest of his life in jail." Jesse Cohen, a Summit, New Jersey, man who called Madoff a "thief and a monster" in a letter to the court, said Tuesday he trusts that the judge will be fair at sentencing. Sorkin said his client has repeatedly cooperated with the government agencies seeking to recover money for victims and figure out how his fraud went undetected for decades. The lawyer said Madoff had met recently for several hours with the inspector general of the Securities and Exchange Commission, providing information and insight into his conduct and the role of the SEC. "The information exchanged during the meeting will no doubt shape and fortify the future of Wall Street regulation and oversight," Sorkin wrote, calling Madoff's participation at the meeting "entirely voluntary." The lawyer included in his submission to the court late Monday an analysis of sentences given to defendants facing a potential life sentence in fraud-related cases between 1999 and 2008 that concluded the average sentence when leniency was not given was 15.3 years in prison. He also noted that Madoff's age would leave him with an average life expectancy of 12.6 more years. In his submission, Sorkin cited dozens of letters from Madoff victims urging Chin to make sure Madoff never gets out of prison. "The significant anger and resentment evidence in the victims' words is no doubt justified in light of the circumstances of this case," Sorkin said. "Thankfully, none of the fury expressed in the victim statements has been as shocking as the death threats and anti-Semitic e-mails that have been directed toward Mr. Madoff and his counsel." Still, he added, the tone of the victim statements "suggests a desire for a type of mob vengeance that, if countenanced here, would negate and render meaningless the role of the court." Sorkin said his office had advised Madoff about the letters and "their tenor and heart-wrenching stories of loss and deprivation." He said he and Madoff acknowledge the "scope and magnitude of those losses and understand the victims' calls for reprisal." Madoff was arrested in December after he confessed to his sons that the private investment side of his business was a fraud. Authorities say Madoff promised investors their accounts were worth as much as $65 billion. In reality, only several hundred million dollars remained.