MR De Rossa looked as if "the stuffing had been knocked out of him" following the Eamon Dunphy article, the Democratic Left deputy, Ms Liz McManus, told the court.
Ms McManus, Minister of State for Housing and Urban Renewal, said she had always had great admiration for Mr De Rossa. It was a major step for the Workers' Party when he became a TD. He was an honest and an honourable man who had total belief in his principles.
She believed the country - not just the party - was lucky to have him as a leader.
Ms McManus said she was absolutely horrified when she read the article. There was absolutely no relation to the Mr De Rossa she knew. She was hurt by it but she also felt very much for him because, in an earlier election, she had been subjected to a "poisoned pen letter herself.
She felt this was another kind of malicious campaign against a good man. He was a man of reserve and not a man to go into a pub and weep into a pint of beer. But it was as if a light went out in him. He had a "bit of a sparkle" when he laughed but that just went.
Ms McManus said the article was appalling. She had written for newspapers and knew the power they had. People believed and accepted whatever was in them.
Asked by Mr Adrian Hardiman SC, for Mr De Rossa, how the article emotionally affected the Democratic Left leader, Ms McManus said she was conscious of the feeling herself. "It was as if the stuffing had been knocked out of him." She did not know when he got back to normal but she could identify with what he had gone through.
"Politically, he had to make it clear this was a total, unwarranted attack; poisonous stuff. I don't know if you can actually fully deal with something like that."
You had to be thick-skinned in politics but this was in a different league. The article was calling him "unspeakable things" when she knew him to be an honest, good man who had spent his adult life working for social justice.
Ms McManus said the article was damaging. The reference to prostitution was particularly inappropriate. Mr De Rossa had his faults but he always treated, women equally. There were times when she believed he was the best feminist in the Dail. The idea of him having any connection with prostitution, exploiting women, was just fantasy in her view.