Rome , Italy -LRB- CNN -RRB- -- The Vatican said a lawsuit accusing it and Pope Benedict XVI of covering up sexual abuse by a priest at a Catholic school in the United States has no merit . `` While legitimate lawsuits have been filed by abuse victims , this is not one of them , '' Vatican lawyer Jeffrey Lena said Friday . `` Instead , the lawsuit represents an attempt to use tragic events as a platform for a broader attack . '' The lawsuit by an unnamed Illinois man demands the Vatican release the names of thousands of Catholic priests that the suit says have `` credible allegations of sexual misconduct '' against them . The alleged victim , who is now an adult , says he was molested by the Rev. Lawrence Murphy while a student at St. John 's School for the Deaf , according to the complaint filed in U.S. District Court in Milwaukee , Wisconsin . `` The defendant , -LSB- the -RSB- Holy See , has known about the widespread problem of childhood sexual abuse committed by its clergy for centuries , but has covered up that abuse and thereby perpetuated the abuse , '' the suit says . `` The case against the Holy See and its officials is completely without merit , '' Lena said . `` Most of the complaint rehashes old theories already rejected by U.S. courts . '' Lena added , `` With regard to Murphy himself , the Holy See and its officials knew nothing of his crimes until decades after the abuse occurred , and had no role whatsoever in causing plaintiff 's injuries . '' Benedict was named as a defendant because he has the ultimate authority to remove priests and because of his involvement in reviewing sex abuse cases when he was Cardinal Joseph Ratzinger , the suit says . Peter Isely , Midwest director of the Survivors Network of those Abused by Priests , estimated the Vatican is investigating 4,000 cases of sex abuse by church employees . The lawsuit aims to change church policies and practices that conceal sex offenders , Isely said . `` It 's going to protect children , we hope , around the world , '' he said , `` This is a historic day and hopefully this is going to result in historic changes . '' Arthur Budzinski , a deaf man who said he was sexually assaulted and raped by Murphy , stood with Isely at a news conference Thursday . He said the priest `` may have stolen our bodies , '' but higher clerics such as cardinals , archbishops and the pope `` stole our voices . '' Budzinski , who is not a party to the lawsuit , made his comments in sign language and his daughter , Gigi , interpreted his words . Murphy , who died in 1998 , is believed to have molested up to 200 boys , Isely said . The lawsuit said the church `` knew that there was a high probability that these clerics would sexually molest more children , but sought to protect itself from scandal , sought to keep its income stream going , at the peril of children . '' Murphy , it says , was a `` top fundraiser and recruiter '' for the church and the `` Holy See wanted to retain Murphy 's services . '' The same Minnesota law firm representing the Illinois plaintiff also filed suit Wednesday on behalf of a Mexican resident who says he was sexually abused by a priest . The suit alleges Catholic officials in Los Angeles , California , aided and abetted the abuse by moving the priest to different dioceses as allegations piled up against him . CNN 's Alan Duke and Hada Messia contributed to this report .