To walk the streets free of the shadow of indictment, to hear a Brooklyn prosecutor last Friday describe the extortion case against him as a tree rotted through, Samuel Kellner might be expected to speak of vindication and hope.  Except this voluble, gray-bearded man cannot summon happiness.  Five years ago, Mr. Kellner, a 52-year-old Hasidic Jew, chose to step off a cultural cliff. He spoke out about the sexual abuse of his 16-year-old son by a prominent Hasidic cantor. And he helped a police detective ferret out other victims of this cantor, whose connections ran to the most powerful reaches of the Satmar community.  Retribution became daily fare for Mr. Kellner. His rabbi denounced him as a traitor. Yeshivas locked out his sons. He pawned his silverware.  Then the former Brooklyn district attorney, Charles J. Hynes, who had proved a most considerate ally of Hasidic leaders, drove a stake into Mr. Kellner’s heart. After gaining a conviction of the cantor, Baruch Lebovits, Brooklyn prosecutors turned around and indicted Mr. Kellner. Basing their case on the questionable testimony of a prominent Satmar supporter of the cantor, they accused Mr. Kellner of trying to shake down Mr. Lebovits.  Mr. Kellner faced decades in prison. He posted bail, only to watch as Mr. Lebovits’s lawyers used his indictment and other technicalities to persuade a state appeals court to overturn the cantor’s conviction.  “My father was an Auschwitz survivor; right away he got sick,” Mr. Kellner recalls. “Within six months, he died. Then my mother had a devastating stroke.”  He pauses, like a sprinter catching his breath. “How do I tell my daddy, ‘I was found not guilty, it was just a libel, just bad people’?” he said. “The government needs to understand it did a pretty good job of killing me.”  There are shards of hope to be found here; even Mr. Kellner acknowledges this. Within days of taking office in January, District Attorney Kenneth P. Thompson assigned a new lawyer to examine Mr. Kellner’s case.  Rotten prosecutions, however, are like an accumulation of cuts. The small community of Hasidic whistle-blowers lives like outcasts. The indictment of Mr. Kellner scarred them.  Mr. Kellner’s lawyers all but begged the state to trial. Mr. Kellner wanted to make a statement that sexual justice, real justice, could be achieved in the Hasidic community.  “We would love to go to trial, because the ugly truth would tumble out,” Niall MacGiollabhui, Mr. Kellner’s lawyer, told the court.  Mr. Lebovits’s supporters spared few riches in his defense, and hired Alan M. Dershowitz, a Harvard professor. Over the years, Mr. Dershowitz and his partners piled up their accusations like so much cordwood. They claimed to discover witnesses against Mr. Kellner, and prevailed upon Mr. Hynes’s longtime favorite, the ex-rackets chief Michael F. Vecchione, to overrule his own prosecutors and try Mr. Kellner.  “We see Kellner as a leader of a major extortion ring,” Mr. Dershowitz told me last year.  In a baroque touch, Mr. Dershowitz appeared in State Supreme Court on Friday and somehow gained admittance to a pretrial conference with the judge, arguing against the dismissal of the Kellner case. This was marvelous theater.  “The idea that a third party — especially on behalf of a criminal defendant accused of crimes by Kellner — could immerse themselves in this case is almost unheard-of, if not comical,” noted Mark A. Bederow, a former Manhattan assistant district attorney.  Mr. Dershowitz roamed the hallway afterward, playing with a grin the more disquieting for the fact that his eyes ran cobalt. He spoke ominously, as he has for years, of new evidence. “This case is not over,” he said. Mr. Kellner “may very well still be going to jail because this tape is the smoking gun.”  Then he suggested that Mr. Kellner’s defense lawyer might appear on an incriminating tape. “A word to the wise,” he said. “Be careful.”  Still, an image that remains from Friday was that of a Hasidic father standing in court, rocking slightly, as an assistant district attorney described wildly inconsistent statements and witnesses who lacked any shred of credibility.  The people, the prosecutor said at last, “do not have a credible case.”  Mr. Kellner’s sons, dark-haired men with long payos, peered at their father, their faces turning red. They greeted him with hugs and laughter. Mr. Kellner even allowed himself a joyous smile.  “I wanted to show to my kids to respect the system,” he said afterward. “I want to tell them, ‘Look, this is the law and it works.’ ”  “It was a message,” he added, “I could not give my own father.”  A version of this article appears in print on March 11, 2014, on page A14 of the New York edition with the headline: After Seeing His Family Crumble, Vindicated Whistle-Blower Has Little to Smile About. Order Reprints|Today's Paper|Subscribe
A judge on Friday dismissed all charges against Samuel Kellner, a Hasidic Jew who has lived as an outcast for years after accusing a prominent cantor of sexually abusing his son.