Maricopa County Sheriff Joe Arpaio on Tuesday said it was "insulting" to point out that members of his Cold Case Posse were profiting off their long-running investigation of President Barack Obama's birth certificate.

"How do you expect any of us to believe any of this?" KPHO-TV's Morgan Loew asked Arpaio at a Tuesday press conference. "You have two investigators who are in business together, and their business is peddling conspiracy theories."

Jerome Corsi of World Net Daily has written numerous books criticizing Obama, claiming he is a radical who is not eligible to be President of the United States. He has co-written a book with former police officer Mike Zullo that questions the authenticity of Obama's birth certificate. Both men are prominent members of Arpaio's Cold Case Posse.

"Well first of all I think that is an insult," Arpaio responded. "A big insult because that's all you want to talk about. You don't want to look at the evidence."

"Sheriff, it would seem that if this were a real investigation you would be saving this for a judge and jury," Loew shot back.

"Well I hope that comes one day," Arpaio said.

Arpaio claims the long-form birth certificate released by President Barack Obama last year was “undoubtedly fraudulent.” He has called for a federal investigation of the issue.

Meanwhile, World Net Daily has been urging its readers to donate money to Arpaio.

Watch video, courtesy of CBS News, below: