Oregon’s top attorney is considering whether to investigate if a crime was committed during the process of putting one of the more controversial initiatives on the November ballot.

At issue is a tax-related measure that could make it harder for Democrats to raise money in the future. The measure, Initiative Petition 31, would require a three-fifths vote of the Legislature for all taxes and fee increases, meaning Democrats without a supermajority would need Republican votes to raise revenue.

The governor is in the midst of working with business and labor groups to keep the measure off the ballot.

Despite calls from some Democratic lawmakers to halt the measure verification process while an investigation is underway, the secretary of state’s office is moving forward with the certification process.

The complaint and investigation could, however, jeopardize the measure’s chance of making it to the ballot.

Stephen Trout, the state’s election director, said the secretary of state’s office will continue to certify the signatures and wait to hear back from the attorney general’s office. After hearing from the attorney general’s office, the secretary of state could consider whether to levy civil penalties.

Trout said his office has until the first week of August to certify the signatures.

“We often get complaints at the last minute,” Trout said, adding that, to his knowledge, it’s never halted the certification process.

The complaint filed by Connea Derber outlines a litany of issues. Derber said she was collecting signatures when she wasn’t certified to do so, she alleges someone else hired by the signature-gathering firm signed the sheets of signatures she collected, and she suggests she was paid based on the number of signatures she was able to collect, which is against the law.

Lee Vasche, who owns Ballot Access — the firm who hired Derber and oversees the signature gathering process — said Derber was being used by Our Oregon, a union-backed group, to stymie the measure.

Vasche, whose business tends to support more conservative measures, and the more liberal Our Oregon have a history of filing election complaints against each other.

“They want to stop this measure,” Vasche said of Our Oregon. “The politicians are passing fee increases. Everything is a fee increase instead of a tax increase and they are skirting the three-fifths requirement. This petition tightens this down … Our Oregon is strongly against that and that’s fine, that’s their prerogative, of course, but they are using the complaint process to score political points.”

Realtors have been pouring hundreds of thousands of dollars into the campaign, in part to ward off the future possibility that lawmakers could curb the mortgage interest and property tax deductions.

In a statement Tuesday, the director of Our Oregon called the incident one of the state’s more significant cases of voter fraud.

“It is unconscionable that the secretary of state refuses to halt the verification process until a thorough investigation into these serious allegations is conducted,” Becca Uherbelau, executive director of Our Oregon, said in a statement.

Dirk VanderHart contributed to this report.