The Minister for Justice, Mr McDowell, has launched a stinging attack on the Republican movement in the aftermath of the £26.5 million Northern Bank robbery that was blamed on the IRA.
In a 3,000-word statement issued this evening, Mr McDowell said the attribution of the robbery to the Provisional IRA was done by the Chief Constable of the PSNI after "careful consideration of the progress of the investigation".
"It was not done with a view to having a political effect," he said.
"I have found Hugh Orde to be a level-headed, professional, and honest police man who is dedicated to the good of the people who rely on the PSNI to uphold the law.
"I have no reason at all to disbelieve or discount his assessment on which the attribution was made.
On the Sinn Féin president, Mr Gerry Adams's statement that he believed IRA denials of the robbery, Mr McDowell asked whether "any sane person" believed that the IRA or Sinn Féin would now acknowledge that it had carried out the robbery.
He said the two organisations had "lied repeatedly" about criminality "when it suited them".
"The Provisionals are in a state of denial about the true implications of the Good Friday Agreement for paramilitarism and criminality," Mr McDowell said.
"Unless the IRA ceases to be an armed paramilitary body; unless it categorically ends for good the activities mentioned by the two Governments in paragraph 13 of their joint declaration; unless its members desist from any activity which endangers the rights and safety of others, there is simply no way open for any political progress for any party or politician who owes allegiance to the IRA or is in any way connected with it."
Minister for Justice, Michael McDowell
Mr McDowell went on to say there could be no room in representative politics or in governmental institutions "anywhere on this island" for any political party or group supports the use or threatened use of force or violence, which possessed arms or explosives, which violently resists the Garda or the PSNI, which engaged in robbery or theft or mutilates by punishment beatings.
The minister said the "massive untruth" at the heart of Sinn Féin was that it claims to operate as an organisation wholly separate from the IRA.
"In fact, as the Taoiseach has said repeatedly, Sinn Féin and the IRA are two sides of one coin. The Independent Monitoring Commission concluded that there was an overlap at senior leadership level between the IRA and Sinn Féin. That confirmed what I had previously said about the presence of household names on the Army Council."
He said it followed that the senior Sinn Féin figures who play a senior role in the IRA were responsible for the "pattern of violence, kidnapping, exiling and torture which the IMC is satisfied are under the control of the IRA's most senior leadership".
"This responsibility must also apply to the recent Northern Bank robbery."
Mr McDowell said the real issue that must now be addressed was the "absolute necessity to bring paramilitarism to a decisive, unambiguous and irreversible end".
"There is little reality in thinking that the IRA will "go back to war". Since the atrocities at the Twin Towers and Madrid, it is abundantly clear that the Provisionals as a movement would face immediate and radical suppression if they were to seriously attempt such a course," he said.
Accusing the Provisional leadership of being "more in the mode of Mugabe than Mandela" and of "ideological kerb-crawling", Mr McDowell said these people were not republican. The had opened up a "gulf of mistrust" and had successfully polarised Northern politics at the expense of those who are reconcilers in the centre ground.
However, he said the door into "exclusively democratic and peaceful politics" is open for them and will remain open.
"But it is not a threshold which can be straddled or camped on by those who want to put one foot into democracy while leaving the other foot planted in terrorism."