Ireland's police colluded with the Catholic church in covering up clerical child abuse in Dublin on a huge scale, according to a damning report on decades of sex crimes committed by priests.

The devastating report on the sexual and physical abuse of children by the clergy in Ireland's capital from 1975 to 2004 accuses four former archbishops, a host of clergy and senior members of the Garda Síochána of a cover-up.

The three-volume report found that the "maintenance of secrecy, the avoidance of scandal, the protection of the reputation of the church and the preservation of its assets" was more important than justice for the victims.

Four former archbishops in Dublin – John Charles McQuaid, who died in 1973, Dermot Ryan, who died in 1984, Kevin McNamara, who died in 1987, and retired Cardinal Desmond Connell – were found to have failed to report their knowledge of child sexual abuse to the Garda from the 1960s to the 1980s. But the report added that all the archbishops of the diocese in the period were aware of complaints.

The report, launched today by the Irish justice minister, Dermot Ahern, also concluded that the vast majority of priests turned a "blind eye" to abuse, although some individuals did bring complaints to superiors, which were not acted upon.

The report, commissioned by the government, strongly criticises the Garda and says senior members of the force regarded priests as being outside their investigative remit. The relationship between some senior gardai and priests and bishops in Dublin was described as "inappropriate".

Rather than investigate complaints from children, gardai simply reported the matter to the Dublin Catholic diocese, the report says. The Garda Síochána is accused of connivance with the church in stifling at least one complaint of abuse and letting the alleged perpetrator flee the country.

Ahern said there should be no hiding place for abusers. "The persons who committed these dreadful crimes will continue to be pursued. They must come to know that there is no hiding place. That justice – even where it may have been delayed – will not be denied," he said.

He told a press conference: "I read the report as justice minister. But on a human level – as a father and as a member of this community – I felt a growing sense of revulsion and anger at the horrible, evil acts committed against children."

The Dublin Rape Crisis Centre welcomed the report, saying it was "another acknowledgment of the abject failure of our society to take care of our children".

The report states that senior clerical figures covered up the abuse over nearly 30 years and that the structures and rules of the church facilitated that cover-up. It says that state authorities facilitated the cover-up by allowing the church to be beyond the reach of the law.

The Murphy Commission of Inquiry into the abuse of children in Dublin identified 320 people who complained of child sexual abuse between 1975 and 2004. It also stated that since May 2004, 130 complaints against priests operating in the Dublin archdiocese had been made.

The report details the cases of 46 priests guilty of abuse as a representative sample of 102 priests within its remit. But it concludes that there was no evidence of an organised paedophile ring in the Dublin archdiocese, although it says there were worrying connections. One priest admitted abusing more than 100 children. Another said he had committed abuse every two weeks for more than 25 years.

The report highlights the case of a Father Carney and Father McCarthy who it claims in one case both abused the same child. The abuse by Carney often occurred at swimming pools, sometimes when he was accompanied by another priest.

The report states that it was not until 1995 that the archdiocese began to notify civil authorities of complaints of abuse. The commission concludes that in the light of this and other facts, every bishop's primary loyalty was to the church itself.

A move by the archdiocese to take out insurance against potential compensation claims arising from abuse, according to the report, proved knowledge of child sexual abuse as a potential major cost.

The Garda Síochána's current commissioner, Fachtna Murphy, said the report made for "difficult and disturbing reading, detailing many instances of sexual abuse and failure … to protect victims."

Pope Benedict was urged today to go to Ireland and apologise for his clergy's behaviour. John Kelly, of Irish Survivors of Child Abuse, said only a papal visit would exonerate the worldwide church in the abuse scandals.

Abuse reports

• October 2005 the Ferns report detailed extensive child abuse and the cover-up of paedophile activity in the south-east of Ireland.

• November 2005 Judge Yvonne Murphy was appointed to head a commission of investigation into clerical child abuse in the Dublin diocese, which concluded today.

• May 2009 the Ryan report detailing abuse at orphanages and industrial schools run by Catholic religious orders across the state was published.