Gov. Nathan Deal vetoed legislation Tuesday that would allow college students to carry concealed guns onto campuses after lawmakers defied his personal request for changes that would make exceptions to the gun rights expansion.

The decision to reject House Bill 859, which would legalize firearms at all public colleges in Georgia, comes almost a month after the governor infuriated many religious conservatives by vetoing "religious liberty" legislation that would have extended legal protections to opponents of same-sex marriages.

"If the intent of HB 859 is to increase safety of students on college campuses, it is highly questionable that such would be the result," Deal wrote in his veto message. He coupled it with an executive order instructing the higher education system to submit a report on campus security measures by August.

The gun measure, known as the "campus carry" bill, was long sought by conservatives and Second Amendment activists who cast it as a crucial safety measure for students, faculty and administrators to protect themselves. Until this year, their efforts were stymied by critics including college presidents, who warn that expanding gun rights to campuses would increase the likelihood of violent shootings.

This year, though, legislative leaders united behind a measure that would allow anyone 21 or older with a weapons license to carry a gun anywhere on a public college or university campus, except for inside four places: dormitories, fraternities and sorority houses, and at athletic events. Everywhere else, including music concert venues and classrooms, would have been open under the bill.

Long an opponent of the measure, Deal said in February that fears that campus carry would lead to a "Wild West scenario" were overblown. But shortly after the measure passed, Deal sent hand-written notes to House Speaker David Ralston and Lt. Gov. Casey Cagle urging them to exempt on-campus child care facilities, faculty or administrative office space and disciplinary meetings in a separate measure. Both declined to make changes, and Deal was soon deluged with personal appeals from Georgians on all sides of the debate.

“Admittedly, it’s another tough decision. Would I have preferred they not put that on my plate (without the changes he advocated)? Yes, I would have preferred that,” he said in an interview before the veto. “But they did. And I have to come, once again, to doing what I think is in the best interest of all the citizens of the state.”

Gun rights groups have vowed to revive the effort. The National Rifle Association singled out Cagle, Ralston and other lawmakers who supported the measure, and said it would work with them again next year "to pass this important safety legislation."

“We agreed with Governor Deal when he said that the arguments against the campus safety bill lacked validity," said NRA spokeswoman Catherine Mortensen. "He was right then, but he is wrong today.”