CHICAGO — A civil lawsuit launched in the United States seeking to tie the Vatican and the Pope to an alleged decades-long cover-up of clergy sex abuse has been dropped, the plaintiff's lawyer said.

The suit was filed in 2010 on behalf of an unnamed victim of an alleged serial pedophile priest called Father Lawrence Murphy, who is accused of molesting up to 200 boys at a school for the deaf in Wisconsin.

It came a month after the victim's lawyer released documents showing that Pope Benedict XVI, then Cardinal Joseph Ratzinger, was made aware of the allegations against Murphy in 1996 but took no action.

Jeffrey Anderson said that while Murphy's abuse was reported to the archbishop in the 1950's and to local law enforcement in 1974, he remained a priest in good standing until his death in 1998.

Already under pressure from a slew of scandals spreading across Europe, the Vatican vigorously defended the pope, arguing that Ratzinger's office chose not to begin defrocking proceedings against Murphy due to his ill health and seclusion.

Anderson, who has filed hundreds of cases on behalf of victims of child sex abuse, said at the time that the purpose of the lawsuit was to gain access to the Vatican's secret files and expose its allegedly systematic protection of abusive clergy worldwide.

The plaintiff decided to drop the case after a judge in a related case ruled on Thursday that Murphy's victims will still be able to seek damages from the Archdiocese of Milwaukee even though it has sought bankruptcy protection, Anderson said.

"Based on our experience in other cases, the road to justice through Rome is a long and arduous one that can go on for decades," Anderson said in a statement after the case was withdrawn late Friday.

"With the development in the bankruptcy case yesterday, the road to justice and healing for this survivor becomes much shorter, and we understand that."

Jeffrey Lena, who represents the Vatican in American litigation, said the dismissal of the case was long overdue and slammed Anderson for "profoundly and unnecessarily" misleading the public by promulgating the "outworn and discredited claim" of a vast cover-up.

"A case like this one against the Holy See, which was held together by no more than a mendacious web of allegations of international conspiracy, amounted to a misuse of judicial process and a waste of judicial resources," Lena said in a statement.

"Mythology about the Catholic Church to the contrary, the Holy See is not responsible for the supervision of the more than 400,000 priests around the world."