She said rules without sanctions were too easily ignored and cases were often swept under the carpet, allowing paedophiles to carry on molesting children.
The symposium is aimed at compelling bishops to create tough policies to protect children and root out paedophiles from the priesthood.
"I would hope that internally there could be some ecclesiastical penalty for a bishop who may not follow the guidelines," the 65-year-old campaigner said at the gathering in Rome. "You obviously have civil law as well, but I am talking more on the church side."
The Vatican sent a letter to bishops last year telling them that they must make it a global priority to tackle the sexual abuse of children by priests and every diocese must draw up its own guidelines in line with local criminal law.
The four-day meeting this week has brought together more than 200 bishops and church leaders to discuss how the church can become more aware of the problem, make a commitment to victims and prevent future cases.
Ms Collins, the only victim attending the conference, spoke in detail about the abuse she suffered at the hands of a priest when she was 13 and how it damaged the rest of her life.
Ms Collins, who was assaulted by a hospital chaplain, told the bishops she had endured multiple hospitalisations later in life for anxiety and depression. She told how the church's response to her abuse -- refusing to believe her and taking the word of the priest -- devastated her.
"I was treated as someone with an agenda against the church, the police investigation was obstructed and the laity misled. I was distraught," she said.
Distraught
In 1996, Ms Collins went to Dublin's then archbishop, Cardinal Desmond Connell, with her story, knowing that the Irish bishops had just adopted a tough new policy to report abusers to gardai. She said Dr Connell told her he didn't have to follow the church guidelines.
Eventually, the priest, the Rev Paul McGennis, was prosecuted and jailed. He was also sentenced twice more for molesting other children.
"The fact that my abuser was a priest added to the great confusion in my mind," she said.
"Those fingers that would abuse my body the night before were the next morning holding and offering me the sacred host."
She said when she tried to warn church leaders about the priest she was ignored on several occasions despite existing church rules on child safety, and he went on to molest others.
"These men can abuse for their whole lifetime, leaving behind them a trail of destroyed lives," she said.
"Coming from a country where guidelines are ignored, I am conscious that as well as having them written down you must have some way of making sure they are implemented."
Psychologists told the assembled bishops that priests who rape and molest children usually lie when confronted with an accusation, and that the church should listen to victims.
Monsignor Stephen Rossetti, a psychologist who for a decade ran a US treatment centre for abusive priests, told the conference that just like alcoholics or drug addicts, sexually abusive priests lie when confronted with allegations. They manipulate, they con, they deny.
As a result, he said, trained civil authorities, not bishops, should determine whether an allegation is well-founded.
Even if prosecutors don't proceed with a criminal case, either because too much time has passed or evidence is lacking, bishops should form an advisory panel of law enforcement, mental health and canon law experts to investigate and decide how to proceed, Msgr Rossetti said.
"When the church listens first to victims, as Pope Benedict repeatedly has done, we learn the truth," he added.