The crash that killed five members of Bluffton University's baseball team was an accident that did not have to happen, officials say.
Last year, the bus carrying the Ohio college students careened off an overpass and onto an Atlanta-area highway.
Now, a National Transportation Safety Board investigation has revealed confusing signs and a lack of safety features caused the March 2 accident.
"Had the appropriate investigation been done at the state level we might not be here today," said NTSB Chairman Mark Rosenker.
Dave Rayburn, an NTSB investigator, says Georgia officials changed the layout of signs near the crash after having trouble mounting them. The change went against federal recommendations of where to place the signs, but did not break any regulations.
Nine other accidents have occurred at the site within the last 10 years. They all involved out-of-state drivers.
Investigators say the bus driver thought he was entering an HOV lane but instead drove onto an elevated exit ramp.
The crash also killed him and his wife, and injured 28 others.
Parents of the victims are calling for stronger safety regulations, including safer buses equipped with stronger roofs, shatterproof windows and mandatory seat belts.