She is the daughter of Judge Joel F. Dubina, Chief Judge of the United States Court of Appeals. Roby attended the New York University and received a Bachelor of Music. She then studied at the Cumberland School of Law at Samford University in Birmingham ( Alabama), which she completed in 2001. Before entering politics, she worked at the law firm of Copeland, Franco, and was a member of a Christian organization.
Roby was first elected to the City Council of Montgomery in 2003. In the elections for the House of Representatives in 2010, she was the Republican candidate in the second electoral district of Alabama. As forecasts initially spoke against it, the Republican sat at the end of almost 51:49 percent of the vote against the democratic mandate holder Bobby Bright by. The mandate of the House of Representatives joined Roby on 3 January 2011.