LOUISVILLE, Ky. (June 14, 2010)—Candidate Rand Paul, who touts his career as a Kentucky eye doctor as part of his outsider credentials in his campaign for U.S. Senate, isn't certified by his profession's leading group.

Paul tried Monday to bat away questions about his certification Monday by calling them an attack on his livelihood, saying the scrutiny stems from his challenge of a powerful medical group over a certification policy he thought was unfair.

The libertarian-leaning Republican helped create a rival certification group more than a decade ago and said the group has since recertified several hundred ophthalmologists, although the American Board of Medical Specialties does not recognize it.

The group governs two-dozen medical specialty boards.

Paul told The Associated Press he was riled by a "hypocritical power play" by the American Board of Ophthalmology that he thought favored older doctors over younger ones.

But the campaign for his Democratic rival says the episode raises questions about Paul's character.