DENVER (CBS4) – The state attorney general’s office is investigating possible fraud in connection with another ballot initiative.

A measure to raise the minimum wage in Colorado to $12 an hour by the year 2020 made the ballot this year, but opponents question whether it should have. The concern comes after a new revelation about potentially forged signatures on one of the petitions.

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This is the second fraud investigation into a ballot initiative process so far this year, and the situation has raised serious questions about Colorado’s petition process.

Lawmakers are already considering changes in how petitions are reviewed in the future.

(credit: CBS)

(credit: CBS)

The signatures in question were all gathered by the same person from the Washington D.C.-based canvassing firm Fieldworks, a person who has a criminal record that includes aggravated robbery.

“If they can’t even be trusted to do background checks how can you trust them to pay the wage they say they’re going to pay,” said Tyler Sandberg with Keep Colorado Working.

Keep Colorado Working opposes the initiative and is calling on the Colorado Secretary of State to review all the signatures on the petitions for the ballot initiative.

“The firm complied with every aspect of law,” said Patty Kupfer, a spokeswoman for the group Colorado Families for a Fair Wage.

Kupfer says the background check didn’t uncover the convictions because it only went back seven years. She says they are cooperating with the attorney general’s investigation.

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“I think if we find — among very small subsample — 5 percent of signatures reviewed and we found fraud there, that makes us concerned that there is much more fraud,” Sandberg said.

Sandberg says supporters of the initiative should welcome a review.

“If they want to prove that there’s not more fraud then they should put it out there and ask the secretary of state and say “Please review all our signatures because we don’t believe there’s fraud,'” he said.

In response to such a suggestion, Kupfer said “We are so confident that we have vastly more than the signatures needed to qualify for the ballot that we would welcome that.”

Colorado Secretary of State Wayne Williams says he doesn’t have statutory authority to conduct a larger review but has put together a bipartisan committee of lawmakers to consider changes in the petition review process, including possible signature verification.

“There’s time and cost involved in this additional review, but I think it’s worth it to ensure that people actually are legitimately on the the ballot and issues are legitimately on the ballot,” Williams said.

Colorado Secretary of State Wayne Williams (credit: CBS)

Colorado Secretary of State Wayne Williams (credit: CBS)

Williams said he is prohibited from doing signature verification now and because the right to petition is protected under the First Amendment, he can’t require background checks.

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Those things could change this next legislative session. In the meantime, the onus is on groups submitting petitions to make sure the canvassers and canvassing firms are ethical.