Anti Austerity Alliance TD Paul Murphy has been released without charge after he was questioned over a water charges protest in which Tánaiste Joan Burton was trapped in her car for over two hours.
The former MEP said the "shocking experience" was designed to "criminalise" protest against the water charges.
Speaking on Claire Byrne Live on RTÉ television, he repeated his claim that his arrest was politically motivated and he denied that he had falsely imprisoned Ms Burton.
The Dublin South-West TD was one of four people arrested over the incident in Jobstown, Tallaght last November.
They were taken to separate garda stations around the city where they were quizzed under section four of the Criminal Justice Act.
The other three, two Anti Austerity Alliance councillors for the Tallaght area - Kieran Mahon and Mick Murphy - and local activist Scott Masterson were also released without charge.
Files will now be sent to the DPP.
Mr Murphy, a member of the Socialist Party, described his arrest as political, but said he was treated courteously during about four hours of questioning at Terenure garda station.
He said he would have co-operated and made himself available for interview, but was never asked.
Mr Murphy criticised gardaí for not contacting him to arrange for him to attend a station for questioning.
However, Junior Minister Simon Harris said the only person politicising the issue was Paul Murphy.
He also said there was not a shred of evidence to suggest this was politically motivated.
He said garda investigations were completely independent and added that no TD should be exempt from an investigation because they were a TD.
Ms Burton was trapped in her car in Tallaght for more than two hours by water charge protesters.
She had been attending a graduation ceremony at An Cosán College in Jobstown when her car was surrounded by protesters who banged on the car and chanted slogans.
Speaking earlier on RTE's Drivetime, Mr Murphy, who was in custody for more than eight hours after being arrested at his home by six gardaí, said he had no doubt that he and the other three arrested would be found not guilty of any charge of false imprisonment.
"Let them charge us, let them have a jury of our peers because we would be found not guilty, unquestionably."
Mr Mahon, a meber of South Dublin County Council, said he was arrested on the allegation of falsely imprisoning Ms Burton.
He said the evidence was of no real substance and he was not able to add anything.
Cllr Mahon said the arrest and subsequent questioning was a "demonisation" of the right to protest.
Socialist Party TD Joe Higgins described the arrests as political policing.
He said the manner in which the four were arrested was designed to denigrate the anti-water charges movement.
Mr Higgins said Mr Murphy had never previously been approached by the gardaí or been asked for a statement.
However, he said he understood there had been a criminal investigation under way into the incident since November.
Minister for Agriculture Simon Coveney rejected the claims of political policing.
"If someone is trapped in their car for a few hours because people are banging on the windows and kicking the doors, well then the guards will take action and I think that is what is happening here," he said.
A spokesperson for the Government declined to comment on the arrests, and said it was an operational matter for gardaí.
Some councillors took part in a walkout during a meeting of South Dublin County Council this evening in protest at the arrests.
It is understood some people who came into the public gallery also took part in the walkout.
The Sinn Féin TD for Dublin South-West, Sean Crowe, said the arrests were over the top.
Mr Crowe said there was criticism of Sinn Fein members that they did not join the walkout, however he said he believed it was just people trying to make political capital.
Meanwhile, protesters temporarily stopped vehicles leaving a car park following a meeting of Fingal County Council.