A former Sinn Féin councillor who interrogated, threatened and waterboarded a man who came to his house to buy a motorcycle has been sentenced to 12 years in prison.

Jonathan Dowdall, 40, and his 60-year-old father, who live on the Navan Road, Dublin, admitted at the Special Criminal Court to falsely imprisoning and threatening to kill Alexander Hurley in January 2015.

Patrick Dowdall was jailed for eight years in prison for his role in the attack.

Ms Justice Isobel Kennedy said today that the video footage depicts a truly terrifying ordeal which no words could convey.

Mr Hurley went to Jonathan Dowdall's Dublin home on 15 January 2015 to buy Jonathan's motorcycle.

But Dowdall believed he was a conman who had paid someone else with a cheque that bounced after researching him online.

When Mr Hurley arrived at the house on the Navan Road, he was tied to a chair in the garage.

Jonathan Dowdall, wearing a balaclava, put a tea towel on Mr Hurley's face and poured buckets of water over him.

Patrick Dowdall took out a silver pliers and threatened to pull off Mr Hurley's fingers, starting with the smallest.

The attack was filmed on a mobile phone and played in court.

The victim can be heard pleading for his life as Dowdall threatened to chop him up and feed him to the Dobermans.

He was tied with white cable ties and told "one more twist and you're dead".

Mr Hurley said he was tortured to the point of death's door and that the psychological injuries will never completely heal.

He said Jonathan Dowdall told him he was a member of the IRA, that there were people watching everywhere, and that if he went to the gardaí he would be picked up in a number of hours.

Jonathan Dowdall is a former Sinn Féin councillor and while the Special Criminal Court heard he was a good friend of Gerry Adams and Mary Lou McDonald, it said it could not see how this could form a threat.

Ms Justice Kennedy said the fact that the attack was recorded by an unknown woman was chilling and the fact that he told the victim that he would if necessary upload it on YouTube shows Jonathan Dowdall's moral compass was skewed.

The court sentenced Jonathan Dowdall to 12 years in prison and his father Patrick to eight years in prison.