The victims' family members on Friday characterized them as motorcycle enthusiasts who were "extremely cautious" drivers.

"This just should never have happened," said James Laymon Sr., the brother of victim Orvil Laymon. "I was just beyond shocked. I do know (Ms. [Sarah Lamb]) killed two of the best people around."

Hamilton County Sheriff's Office spokeswoman Janice Atkinson said the new indictment comes in the wake of toxicology reports indicating Ms. Lamb was drunk at the time of the April accident. She also is charged with four counts of reckless endangerment, driving on a revoked license and third-offense DUI, Ms. Atkinson said.

"The accident could have been a lot worse," Mr. Laymon Sr. said. "This girl was an accident waiting to happen."