Roberts joined CNN, a cable-news channel, in December 2001 and was based in Atlanta, Georgia. He was a weekday anchor on CNN Headline News, co-anchoring alongside Judy Fortin, Sophia Choi, and Kathleen Kennedy. He co-anchored the CNN Headline News coverage of the 2003 Space Shuttle Columbia disaster and the channel's ongoing Iraq War coverage. He received an Emmy Award nomination in 2002 for his investigation into a local puppy mill that was eventually shut down due to his reporting, according to his profile at CNN. He resigned from CNN on May 1, 2007, to pursue "new journalistic opportunities" in the Washington, D.C. area and to be with his partner.