(CNN) -- Former CNN anchor Lou Dobbs said Thursday said neither he nor his companies have ever hired illegal immigrants and it was not his responsibility to check their papers.
Dobbs challenged an online article accusing him of hiring contractors who employ illegal immigrants on his properties.
During his afternoon show on WOR NewsTalk Radio 710 in New York, he and Isabel Macdonald, author of The Nation piece, debated what he should have done to ensure the workers were in the United States legally.
Dobbs, who left CNN in November 2009, repeatedly asked Macdonald whether he or his companies had ever hired an illegal immigrant.
"No," she said.
But Macdonald said that the situation involved Dobbs and his Dobbs Group hiring contractors that she said used undocumented workers. She pressed the journalist on whether he had ever checked on the status of workers at his properties.
Dobbs, who called the article a "hit piece," countered that he had no legal right to do so.
"They want me checking citizenship and status?," he said later in his show. "I don't think so," adding he could be sued for stepping in.
"I have documented that undocumented workers have been fundamental in the maintenance of your estate in West Palm Beach," said Macdonald.
The talk show host said workers at his New Jersey farm receive health and retirement benefits.
"You can understand my sensitivity in you going after my 22-year-old daughter. That doesn't sit well with me," Dobbs told the author.
He defended the hiring of those working at the stables. "I have been told they are absolutely legal."
Macdonald said Dobbs is responsible for those working at his properties.
"I didn't hire him directly," Dobbs replied to a claim that an undocumented Guatemalan was paid $8 an hour to watch his grounds. "I didn't hire him undirectly."
In the article posted Wednesday on The Nation's website and headlined "Lou Dobbs, American Hypocrite," the leftist political magazine reports that Dobbs hired contractors who used illegal immigrants for landscaping work and caring for horses ridden by his daughter, Hillary Dobbs, a champion show jumper.
It says the landscaping and equestrian industries depend on illegal immigrants due to the low pay, long hours and physical labor. In the article, several people identified as current or former workers on Dobbs' properties say they were in the United States illegally at the time.
However, the article says none of the names reported for the workers are real because they requested aliases to prevent their possible deportation or firing.
Dobbs has a history of making critical comments about the high number of illegal immigrants and the way they are treated. In particular, he has said that employers who hire illegal immigrants should be prosecuted.
"Why not make it a felony for illegal employers who hire illegal aliens?" Dobbs asked on his CNN show on April 4, 2006.
The next day, he said on his show that field workers are paid "not, in my opinion, an adequate wage, but a decent wage," adding: "These people deserve to be paid more. And we're sitting here talking about more of the same, allowing people to be exploited in this country."
The Nation article reports that one worker said he crossed the Yuma Desert on foot from Mexico five years ago, eluding the border patrol, in order to find work.
According to the article, the man said an old friend worked at a stable owned by Dobbs and promised the man work as a groom at a Vermont stable contracted to care for horses owned by the Dobbs Group, which is headed by Dobbs.
The man held the job for more than two years without legal documentation, the article says, adding that he then obtained a guest-worker visa, designed for seasonal foreign workers. The article says Dobbs on his CNN show had denounced such visas as a form of "indentured servitude."
Another man whom the article says cared for Dobbs Group horses is quoted as saying the job required him to be available at all hours, day and night. "I looked after Dobbs' horses while I was illegal," the article quotes him as saying.
Several workers are quoted in the article as saying they believe that Hillary Dobbs knew about their lack of legal papers. The article says she "did not respond to repeated attempts to contact her for comment."
The Nation identified Macdonald as a freelance journalist and former communications director of the media watch group Fairness and Accuracy in Reporting. It was reported with research support by the Investigative Fund at The Nation Institute, according to the website post.
"You put out an article that is being used by the left-wing press as a hammer on me," Dobbs told Macdonald. "And you know full well, you already acknowledge, I never hired illegal immigrants, my company never has and I don't condone it."
Dobbs and Macdonald had a testy exchange at the end of the WOR segment.
"Your listeners deserve to know the truth," said Macdonald.
"Come back and next time concentrate on truth, reality and straight-forwardness," Dobbs replied.
The pair continued the debate Thursday night on MSNBC's "The Last Word."
"Even Lou Dobbs, the emblem of this get-tough approach on immigration enforcement, even he has been unable to manage his property [so that] there will be no undocumented workers," Macdonald said.
Dobbs said he has done nothing wrong and is being targeted. He also said the article omitted the fact that he is seeking a compromise on immigration issues.
Dobbs did not return calls from CNN seeking comment Thursday.