There will be a three-tier disciplinary process for gardaí under the new Garda inspectorate legislation, according to the Minister for Justice.
Mr McDowell said the legislation would be published next year.
Speaking at the graduation ceremony for 118 new members of the force in Templemore yesterday, Mr McDowell said he wanted to ensure that there was a system in place to ensure that abuses like those alleged in Donegal did not take place, and where they did those involved would face appropriate action.
"I want to ensure that the admirable quality of loyalty to one's colleagues does not turn into complicity," he told journalists after the ceremony.
"I told the graduates that their first loyalty was to the force and the community."
He said that the new inspectorate would comprise a fully independent three-person body, which would have its own trained investigation staff.
It would have extensive powers to investigate independently complaints against members of the force, which would give it the powers of an Ombudsman.
It would also have general oversight of police operating standards.
Not all complaints against gardaí would be investigated by this body, he said. Minor disciplinary matters, involving allegations like rudeness, would continue to be dealt with internally within the Garda Síochána.
More serious allegations would also be dealt with internally, but with oversight by the independent inspectorate, he said. The most serious allegations would be dealt with by the inspectorate itself, which would have its own trained investigation staff, not necessarily drawn from among police officers.
It would not be an option not to co-operate with the new inspectorate, he said. This would be written into the legislation.
"People do not have the option not to co-operate with tribunals or with High Court inspectors."
Mr McDowell said he took "very seriously" the suggestion from the chairman of the Garda Síochána Complaints Board that there had not been full co-operation with it from members of the force involved in policing the Reclaim the Streets demonstration last May.
He added that he had not yet seen either the report from the board or the report of the Garda investigation by Assistant Commissioner Hickey.
The Garda Commissioner, Mr Pat Byrne, said that the legislation establishing the Garda Complaints Board contained a mechanism whereby the co-operation of gardaí could be obtained.
"It is not for me to say why the Garda Complaints Board did not use it," he said.
He also said he had not yet read the report from the board.
Mr McDowell also described three new non-lethal weapons that will be issued to the Emergency Response Unit, which will be trained to use them.
Such weapons are intended to avoid, when possible, a situation like the shooting dead of John Carthy in Abbeylara.