Justice Minister Alan Shatter insisted sexual assault cases will be fully investigated amid allegations that officers threatened to rape protesters at the controversial Corrib gas project.
The Garda Ombudsman took the unusual step of launching a public interest inquiry over the accusations that a sergeant and two colleagues laughed about sex attacks on two women at the gas scheme in north Mayo owned by energy giant Shell.
Their damning conversation was inadvertently taped after a video camera seized from the activists was left recording in the back of a patrol car.
While Mr Shatter said he did not want to prejudge the outcome of any investigation into the allegations, he said it was important that gardai were respectful when dealing with the public.
"I want to assure anyone who is a victim of a sexual offence or rape that they will get a full and proper considered approach from the Garda Siochana," Mr Shatter said.
"That they should not have any doubt about that, that if they are a victim of any sexual offence, it will be fully and properly investigated."
Garda Commissioner Martin Callinan said last night that professionalism, sensitivity and compassion were key to the investigation of sexual crimes.
"An Garda Siochana will continue to work closely with support organisations for victims of sexual crime and other victim support groups to ensure that our policy and approach to the investigation of sexual crime meets, first and foremost, the needs of victims," he said in a statement.
He added: "We have stated clearly in the past and I want to say again that a positive and compassionate attitude from members of An Garda Siochana is vital.
"That is our clear policy. That is the message delivered in our training. That is what we expect of gardai."
Amnesty International, Rape Crisis Network Ireland and politicians accused the officers of an abuse of power and breach of trust.
The recorded conversation includes threats to deport and rape one of the protesters who refused to give her name.
One garda starts the conversation off by saying that one of the women "sounds like a Yank or Canadian".
Another officer joins in: "Well, whoever, we'll get immigration f****** on her."
A more senior garda, understood to be a sergeant, adds: "She refused to give her name and address and was told she would be arrested."
A colleague joins in: "And deported."
Before the sergeant says: "And raped."
Community group Pobal Chill Chomain said the alleged comments must not be tolerated in a civil society, and called for the officers to be removed from active duty.
"As a community group in the afflicted area, Pobal Chill Chomain calls on Justice Minister Alan Shatter to initiate an immediate investigation into these matters," the body said.
A superintendent from outside Co Mayo has been brought in to oversee an internal investigation into the allegations.
Formal complaints are to be lodged with the Garda Ombudsman from the two women and also Sinn Fein.
The unnamed protester said she would be back at the Mayo protests, now in their eighth year, despite worries over what the gardai said and publicising the recording.
Corrib has been the most bitterly divisive industrial project in Ireland for a decade.
Some opponents criticise the State contract with Shell which guarantees the energy giant massively profits from natural gas fields containing supplies worth tens of millions, if not billions, of euro.
Locals have fought for years over the pipeline route in the north Mayo Gaeltacht - across bogland, near isolated homes and through Sruwaddacon Bay, an area of outstanding beauty, and the high pressure being used to pump gas onshore.
Mr Shatter said he believed it was in the national interest that the project proceeds.
"I think that it is unacceptable that a small group can effectively obstruct or create unnecessary difficulty in the lawful development such as is taking place down there and indeed bringing ashore essential natural resources that can be to the economic benefit to this state," he told RTE radio.
Five men, the Rossport Five, spent 94 days in jail in 2005 after refusing to agree not to protest.
One of them, Willie Corduff, was badly beaten by a private security firm in a late-night sit-down protest in 2009.
There have been 111 complaints to the Garda Ombudsman over policing at Corrib - 78 were deemed admissible and seven files were sent to the Director of Public Prosecutions.
One file, dealing with a number of incidents and officers, was sent to the Garda Commissioner's office calling for disciplinary procedures.
No action has been taken. The ombudsman's public interest inquiry is only the sixth of its kind since the office was officially opened in May 2007.
Following the publication of the recording, an observer from the Frontline human rights group is to be sent to Mayo to monitor policing.
During the conversation the officers appear to egg each other on.
The senior officer says: "Give me your name and address or I'll rape you."
There is laughter and another officer says: "Hold it there, give me your name and address there, I'll rape you."
The senior replies: "Or I'll definitely rape you."
Susan McKay, chief executive of the National Women's Council of Ireland, called on Commissioner Callinan to act immediately against the officers at the centre of the scandal.