CHICAGO, Dec. 4, 2012 /PRNewswire/ -- A suit filed in Cook County (IL) Circuit Court today accuses the Boy Scouts of America (BSA) and the Chicago Area Council of failing to protect scouts against a serial pedophile who is now serving a 100-year prison sentence in Illinois. The suit alleges that the Boy Scouts were aware of former scoutmaster Thomas Hacker's arrest in Indiana for sexual assault and battery of boys as early as February, 1970. Yet because of Scouting's inadequate screening system, Hacker re-surfaced as a scoutmaster in Illinois and continued molesting boys for the better part of two decades after that. (Logo: http://photos.prnewswire.com/prnh/20121204/CG23963LOGO) Hacker, now 75, was convicted in 1989 of five counts of aggravated criminal sexual assault against three scouts, and was sentenced to two concurrent 50-year terms. Hacker is described by author Patrick Boyle in a 1995 book, Scout's Honor: Sexual Abuse in America's Most Trusted Institution, as "the most prolific molester in Scouting: He moved among troops and schools for 25 years, molesting, by his estimate, 'well over 100' boys." Representing plaintiff " John Doe," who wishes to remain anonymous, are Chicago attorneys Christopher T. Hurley and Evan Smola, of Hurley McKenna & Mertz P.C. The firm has handled a wide variety of sexual abuse cases, including cases against the Catholic Church, the Archdiocese of Chicago, the Irish Christian Brothers and the Boy Scouts of America. The plaintiff in this case grew up in Burbank, and was a Cub Scout through the early 1980s before becoming a Boy Scout. The alleged instances of molestation occurred in 1985 "on routine occasions during, before, or after various Scouting activities," when the plaintiff was ten years old, according to the lawsuit. What the scout and his parents didn't know, and couldn't have known, was that his scoutmaster was already a convicted pedophile who had been banned from Scouting in Indiana. "This is an egregious case of our client being let down by the informal and ineffective system Scouting had in place to protect its members," said plaintiff's attorney Chris Hurley. He continued, "While BSA was promoting the wholesomeness of its programs, and its moral and safe environment, for decades it was secretly removing scoutmasters for child sexual abuse at an alarming rate. Unfortunately, once removed, many of them managed to sneak back in and continue victimizing boys." In the case of Thomas Hacker, recently-released documents – the so-called "perversion files" – show that BSA established a confidential file on Hacker by June, 1970, based on reports that he had been "arrested [in Indiana] for homosexual activity with many boys both in Scouting and through the school in which he was teaching." Even though the arrest led to a felony conviction, Hacker re-appeared in Scouting in 1971, in the Chicago area, as a scoutmaster with the Northwest Suburban Council. By late 1971, BSA learned that Hacker had again been arrested on charges of taking indecent liberties with a child. A BSA official indicated that "under no circumstances do we want [Hacker] registered in Scouting." Yet sure enough, Hacker re-surfaced as a committee chairman and scoutmaster in the Chicago Area Council in 1983 or 1984. The lawsuit contends that BSA did not conduct a background check at the time Hacker registered with the Chicago Area Council. Through his position with the Council, the suit maintains, Hacker gained access to many more young boys, including the plaintiff, and continued to molest.