There were testy exchanges as lawyers for the BBC repeatedly asked Gerry Adams to comment on the litany of atrocities carried out by the Provisional IRA during the troubles in Northern Ireland, estimated at around 1,700. Senior counsel Paul Gallagher, for the BBC, brought Adams through a series of killings in the 1970s from vigilante killings of Catholics and the murder of a magistrate to Bloody Friday, and the Kingsmill massacre. Many of the incidents the former Sinn Féin president could recall, but some he could not. Or not in detail. He described the Abercorn Restaurant bombing in March 1972…