One of the civil cases, all taken against both O'Grady and the diocese of Cashel and Emly, alleges that he sexually abused a child while a seminarian at St Patrick's Seminary in Thurles. "One of the cases we've taken concerns abuse by O'Grady of an Irish kid in Thurles before he came to the US, " attorney Patrick Wall, of Manly, McGuire & Stewart in California, told the Sunday Tribune.

The other two civil actions concern people who allege they were abused by O'Grady as children while he was living and working in the Stockton diocese in California.

"I've met O'Grady, " Wall said. "He's the Hannibal Lecter of the clerical world.

The most dangerous thing about him is his appetite and preference for abusing just about everyone. He's admitted to abusing post and prepubescent boys and girls. He's even slept with adults in a bid to get closer to their children".

Wall said there was strong evidence to suggest that some Irish church authorities knew that O'Grady was a paedophile while he was still in St Patrick's Seminary in Thurles. This was the basis for the civil action against the Irish diocese in relation to the two lawsuits by people who allege abuse by O'Grady in the US.

O'Grady has been served with notice of the lawsuits at his home on the North Circular Road in Dublin's Phibsborough in the past few weeks. Wall said that notification of the legal proceedings to the diocese of Cashel and Emly had been initiated through the Hague Convention. "The diocese may not have been informed yet but notification should be with them soon."

A spokesman for the diocese said they had not received any notification relating to three lawsuits initiated in the US. He pointed out that a similar civil action taken by the same law firm against Cashel and Emly was dismissed on 27 December 2006. The case concerned an individual who alleged abuse by O'Grady in California. The court's finding is under appeal by Manly, McGuire & Stewart.

In May 2005, the Stockton diocese paid out $3m ( 2.5m) to a former altar boy who was abused by O'Grady. The diocese has paid out a total of $14m ( 10.2m) to victims of O'Grady, who pleaded guilty in 1993 to abusing two brothers.

O'Grady was deported to Ireland in 2000 after serving seven years in prison and is now living on Dublin's North Circular Road.

Solicitors representing O'Grady were unavailable to comment when contacted last week.

Wall, once a Benedictine monk, left the church after he became disillusioned with the way they dealt with clerical sex abuse scandals. He was part of a clerical team assigned to deal with the fallout from abuse scandals. "It was really a cover-up and damage control operation, " he said.

Now married, Wall has worked on over 600 clerical sexual abuse cases. "O'Grady is by far the most dangerous of all the clerical abusers I've dealt with and he remains a danger, " he added.