People who were abused by US Roman Catholic priests held a small protest in Rome against a Mass celebrated by a major figure in the sex abuse scandal.
Blaine said Law's image brought out victims' hurt and pain
Two leaders of a victims' support group were escorted from St Peter's Square as they tried to hand out leaflets.
Cardinal Bernard Law - the former archbishop of Boston - is celebrating a Mass of mourning for Pope John Paul II.
He resigned from his Boston post in 2002 after accusations that he covered up sexual abuse of children by priests.
The only US figure leading one of the nine Requiem Masses, Cardinal Law remains an influential Church figure.
Cardinals have decided not to speak to the press before beginning the conclave to elect a new pope, so Cardinal Law's public appearance is one of few chances to hear an elector speak before the voting begins.
He is celebrating the Mass because he is archpriest of the St Mary Major Basilica, a position the late Pope appointed him to after he left Boston.
More than 100 cardinals met on Monday morning to keep the daily business of the Church running while there is no pope.
Barbara Blaine, founder of the Survivor's Network of the Abused by Priests (SNAP), and colleague Barbara Dorris were moved off the square by police as they distributed leaflets in English and Italian ahead of the Mass.
Law was once considered a possible future pope
Neither police officials nor protesters made any immediate comment on the incident.
But Ms Blaine said in a news conference after her arrival in Rome that Cardinal Law's participation in the service was distracting attention from mourning for the Pope.
"We are the sons and daughters of the Catholic family who were raped, sodomised and sexually molested by priests," she said.
Cardinal Law's presence was like "having the sex-abuse scandal in our faces", she added.
James Post, the president of another advocacy group, the Voice of the Faithful, said: "Cardinal Law continues to be the living symbol of the blackish blemish on John Paul II's papacy."
The US Conference of Catholic Bishops and Cardinal Law himself have declined to comment on the affair, though he has apologised for "decisions which led to suffering" and resigned as archbishop in December 2002.
He is eligible to vote for the new pope. Before the scandal, he had been considered a possible future pope - the first US pontiff.
The Boston Archdiocese avoided bankruptcy by agreeing to sell land and buildings for over $100m to fund legal settlements to more than 500 abuse victims.
In February 2004, a report commissioned by the Church said more than 4,000 US Roman Catholic priests had faced sexual abuse allegations in the previous 50 years, in cases involving more than 10,000 children - mostly boys.