David Eric Yellen, 59, of Royal Oak, was charged in June of last year after federal officials found hundreds of files of child pornography on his electronic devices. The FBI learned Yellen was using a peer-to-peer file-sharing software called BitTorrent to distribute the images.

He had worked as a photographer and videographer at several youth gymnastics events over multiple years. When officials searched his devices, they found at least 200 images of the bare feet of children who had attended the gymnastics events, according to U.S. Attorney Dawn Ison.

These photos were in a folder labeled "BFK," which stood for "Barefoot Kids."

Last year, Yellen had said he used BitTorrent but denied uploading or downloading child pornography.