The head of the RUC in Derry, Supt Frank Lagan, was shocked when he learned that British army commanders hoped to arrest up to 500 rioters if there was trouble during the civil rights march on January 30th, 1972, the inquiry heard yesterday.
Supt Lagan's strong advice that the march should be allowed to proceed to the city centre had already been overruled, both by his chief constable and by Gen Robert Ford, the commander of land forces.
But according to notes referred to yesterday by the tribunal's counsel, Mr Christopher Clarke, the superintendent "seems to have been stunned by the size of the proposed arrest operation". At a briefing meeting, he asked what arrangements had been made to handle such a large number of prisoners, but was told that that was a police responsibility.
As Mr Clarke continued to outline documents so far uncovered in relation to military and political planning for the Bloody Sunday march, it emerged that Gen Ford seemed to be the officer most determined that a large "scoop-up" operation should be mounted to capture hundreds of "hooligans".
However, Gen Ford left the details of the scoop-up operation to the brigade commander in charge on the day, Brig Andrew MacLellan, OC of the 8th Infantry Brigade. He ordered him to prepare a detailed plan and subsequently approved an order governing the deployment of troops.
Mr Clarke said it appeared that the decision on how the march should be dealt with was effectively taken at a meeting at Army HQ, Northern Ireland, on January 26th, four days before Bloody Sunday.
Mr Clarke referred to a conflict of evidence between Supt Lagan and Brig MacLellan on whether they had shared the view that the march should not be blocked.
The two discussed the forthcoming march at a meeting on January 24th. Supt Lagan subsequently gave evidence to the Widgery Tribunal that he believed the brigadier had agreed with his own view that the march should be allowed to proceed to the Guildhall and that those involved should be photographed and prosecuted afterwards.
However, in a letter to Gen Ford on March 15th, six weeks after Bloody Sunday, Brig MacLellan described the police officer's evidence on this point as "thoroughly misleading."
In his letter, which has been produced to the tribunal, the brigadier wrote: "Our discussion centred around the probable consequences of stopping the march, in order that we could anticipate the steps that we should have to take. The question of whether the march should or should not be stopped was academic.
"As you well know Lagan's sympathies (and those of his deputy, McCullough, who was also present at our meeting) lie entirely with the Catholic community. His proposal that the march should be allowed to proceed was patently a gesture, or `umbrella', to maintain his position with his own people."
Brig MacLellan asserted that "it was well known to both of us" that subsequent arrests would be virtually impossible, and that "the government were bound to decide that the march should be stopped, and that the Joint Security Committee would share this view".