Independent deputy Finian McGrath said the man, who was very distraught and said he was an abuse victim that no one cared about, had come to the Dáil to attempt to take his own life for a reason.
“I was talking on the plinth with some journalists when we saw a man climb on the railings,” said Mr McGrath. “Initially I thought he was trying to put a banner up, or climb over, which happens sometimes. Then we looked again and said, ‘Jesus, there’s something wrong’, and we ran down to see if we could help.”
Mr McGrath revealed that it took at least four people to save the man’s life.
“As we did, a guard ran over and grabbed the guy by the knees, then I and another man grabbed him by the legs to try and keep him up.
“We had to get a good grip to hold him up, he was quite heavy. A member of the public came over to help, then the man was cut free and we lifted him down.
“He was not violent, just very, very distraught. He was really crying and talking about being abused and that nobody cared, it was very sad.
“The guards were very gentle with him, but he had to be restrained because he was very upset and tried to throw himself under a car.”
Mr McGrath insisted the incident highlighted the need for more resources to be put into suicide prevention and mental health care.
“He came to the Dáil to hang himself on the Dáil railings for a reason. He was very distraught, well dressed. He obviously had serious mental health issues.
“It brings it home to you when it is right at the gates of the Dáil. A lot of people are not getting the care and help that they need and deserve and the Government needs to wake up to that.
“I hope that man gets proper care and attention now. The pain of his situation was all over his face,” Mr McGrath said.
The TD said Leinster House authorities had offered him, and other people involved in the incident, counselling, but he had declined.
“It was upsetting at the time, but I am just so happy and relieved that he did not die there,” Mr McGrath said.
Leinster House authorities said they could not comment on the matter as it was in the hands of the gardaí.
A spokesperson for the gardaí said: “A man in his 40s was taken to St James’ Hospital following an incident at Leinster House.”
The death of homeless man Jonathan Corrie, metres from the Dáil last December, forced the Government into rapid action to deal with growing numbers of people sleeping rough in the run-up to Christmas.