Under the proposal, Arkansas would have provided free photo IDs to voters who don't have one, costing the state an estimated $300,000. The requirement would not be enforced until funding is available for the IDs or Jan. 1, 2014, whichever occurs last.
Beebe, a Democrat who formerly served as attorney general, issued the opinion shortly after Attorney General Dustin McDaniel released an advisory opinion saying he couldn't predict whether a court would find the restriction unconstitutional. But Beebe said any new voting restrictions should be justified "by the most compelling of reasons."
"This is particularly so when the citizens, whose right to vote is most likely to be impaired, are those citizens who experience the most difficulty voting in the first place: the elderly and the poor," Beebe wrote in his veto letter. "A compelling justification should likewise be shown when the citizens most likely to be affected include minorities who have in the past been the target of officially sanctioned efforts to bar or discourage them from participating in the electoral process."
Beebe also said Arkansas would be placed on the hook for ongoing expenses.
"At a time when some argue for the reduction of unnecessary bureaucracy and for reduced government spending, I find it ironic to be presented with a bill that increases government bureaucracy and increases government expenditures, all to address a need that has not been demonstrated," Beebe wrote. "I cannot approve such an unnecessary measure that would negatively impact one of our most precious rights as citizens."
Under the current law, if voters refuse to show an ID card they may vote a provisional ballot that must later be verified by election workers. Under the proposed law, voters could still file a provisional ballot but it would not be counted until they provided an ID to county election officials or, before noon on the Monday following an election, signed an affidavit stating they are indigent or have a religious objection to being photographed.
Republicans around the country have been pushing for similar laws, though the measures have faced court challenges. Voter ID laws in Wisconsin and Pennsylvania have been blocked.
Arkansas Republicans had pushed for voter ID requirements for years, but the measure failed to reach the governor's desk under Democratic majorities. Republicans last November won control of the Legislature for the first time in 138 years and have enjoyed a number of successes, including the passage of stricter anti-abortion laws and broader gun rights.
The Republican-led Legislature already has overridden Beebe's vetoes of two abortion restrictions, including one that would ban the procedure 12 weeks into a pregnancy.
Sen. Bryan King, the Republican behind the bill, did not immediately return a call seeking comment but has previously said he'd seek an override if Beebe rejected the measure.
"In order to ensure the fairness and integrity of Arkansas elections, we look forward to overriding this veto in the days to come," state Republican Party Chairman Doyle Webb said.
If the override is successful, Arkansas would join four other states with a strict photo ID requirement for voters, according to the National Conference of State Legislatures. Virginia lawmakers have sent that state's governor a similar photo ID bill. Similar restrictions by Texas and South Carolina have been rejected by the federal government under the Voting Rights Act, and Mississippi is waiting for federal approval of its photo ID law.
The American Civil Liberties Union of Arkansas has called the requirement unconstitutional, and its executive director said the group was looking at its options after lawmakers gave the measure final approval.
Opponents of the measure had unsuccessfully challenged the way it was approved in the Legislature, saying it changed Arkansas' voter-registration system and therefore needed a two-thirds vote in both chambers to pass. The Senate rejected that recommendation from its Rules Committee shortly before giving the measure final approval last week. A House panel had rejected the same argument earlier in the month.
Black lawmakers in both chambers have spoken out against the bill, comparing it to poll taxes levied during the Jim Crow era.
"I think it's going to have impact on a lot of voters, not just African American voters," said Sen. Stephanie Flowers, D-Pine Bluff, who voted against the proposal. "When you look at the historical context of voting rights in the context and in Arkansas, you can't just dismiss that. That's why we have such a strong law."
Beebe's office has said the governor's concerns centered on whether it imposed a new qualification for voters, not on the procedural questions about how many votes it needed to pass.
It is rare for Arkansas voters to cast provisional votes, and even rarer for them to be counted. In the 2008 and 2010 general elections, less than one-quarter of 1 percent of Arkansas ballots were cast provisionally, and fewer than half of those were ultimately counted. Final data for the 2012 election was not immediately available.