He grew up in Maplewood, New Jersey and attended Saint Benedict's Preparatory School in Newark.
[4] He was admitted to the bar in New York and New Jersey, concentrating in his legal career on corporate and insurance law.
He worked for the Home Insurance Company in New York City from 1982 to 1987, serving as senior vice president for government affairs and associate general counsel.
[14] While serving as County Executive in 2000, Treffinger and Essex County Sheriff Armando Fontoura banned the television show, The Sopranos, from filming on county-owned property due to safety concerns and displeasure over the show's portrayal of Italian Americans.
[15][16][17] On April 18, 2002, agents from the Federal Bureau of Investigation and the Internal Revenue Service raided Treffinger's county office, carting away boxes of files, computers, and other materials.
U.S. Attorney Chris Christie announced that Treffinger had been charged in a 20-count indictment with extortion, fraud, obstructing a federal investigation and conspiracy.
[19][20] On May 31, 2003, shortly before his trial was scheduled to begin, Treffinger pleaded guilty to one count of obstruction of justice and one count of mail fraud, admitting that he had solicited an illegal $15,000 campaign contribution in exchange for a county contract, and that he had placed two people on the Essex County payroll who instead worked on his 2000 Senate campaign.
[28] In November 2007, it was reported that Treffinger had enrolled at the Princeton Theological Seminary and was planning to start a ministry for prison inmates.