Voters reject ballot measure capping Colorado’s income tax rate at 4.4%

Colorado voters rejected a ballot measure that would have established a maximum state income tax rate of 4.4% — a political ploy designed to prevent a separate ballot initiative from raising taxes on higher earners.

Proposition 136, brought by conservative political nonprofit Advance Colorado, was trailing 52.7% to 47.3% as of 9:41 a.m. Friday, when the race was called by The Associated Press.

On its own, Proposition 136 would not have had any tangible effect on state taxpayers. The state income tax rate is already 4.4%, and in Colorado, taxes can’t be increased without voter approval.

Instead, the proposition was aimed at blocking another measure on the November ballot, Amendment 87, a proposal from liberal groups to impose a graduated income tax in Colorado. 

Colorado Dawn and Common Sense America, two conservative political nonprofits that don’t disclose their donors, spent hundreds of thousands of dollars to collect signatures to get Proposition 136 on the statewide ballot.

If voters had approved both measures, they would have been in conflict with one another. And historically, courts have held that if two conflicting measures pass, the one with the most votes takes precedence over the other.

As of Friday morning at 10 a.m., The Associated Press had not called Amendment 87. But supporters declared victory at a Thursday afternoon press conference, and the measure’s opponents conceded defeat early Friday morning.

Amendment 87 will implement graduated income tax brackets that would raise taxes on households and businesses earning more than $500,000 a year. The liberal groups supporting Amendment 87 opposed Proposition 136, arguing that it was designed to confuse voters.

With the defeat of Proposition 136, the state avoids a legal dispute over how to reconcile the six tax brackets in Amendment 87 with the proposed income tax limit.

Colorado Sun staff writer Jesse Paul contributed to this report.