Mr Daly said Mr O'Brien lost control of the bicycle and fell on to the road. He tried to get up and fell again. As he attempted to get to his feet a second time he was hit by a passing motorist who failed to stop.
He told Judge Matthew Deery that O'Brien, of Balbutcher Lane, Ballymun, Dublin, had enthusiastically celebrated St Patrick's Day at a party in his brother's house. He had taken a bicycle from next door and had set off after 3am to go home.
Mr Daly said Mr O'Brien fell off the bike in Balbutcher Road. He stumbled and fell a second time before being hit by the passing car.
Mr O'Brien told the court he may have hit a kerb with the bicycle wheel.
The car hit him on his left side, injuring his kidney. Blood was found in his urine after he was taken to the Mater Hospital.
Judge Deery awarded O'Brien €20,336 damages, but said, because of the situation he had put himself in at the time, he would deduct 30pc for contributory negligence, reducing the amount to €14,235.
He said Mr O'Brien had admitted to having drunk 10 Budweisers and there may well have been more. He had been on his hands and knees when the car struck him.
Judge Deery said CCTV footage of the incident was unhelpful, but accepted that the serious kidney injury suggested he had not simply fallen off the bicycle.
"Mr O'Brien, in electing to cycle home at that time of the morning and having consumed so much alcohol, put himself in the way of injury," Judge Deery said.
The driver of the car that had struck him would have had some opportunity of seeing him on the roadway.
He had suffered a serious kidney trauma and had been in hospital for five days.