We’ve mentioned that Colorado has been an outlier high-growth blue state, largely because of its constitutional spending limits and low flat-rate tax.

The ballot measure Prop 87 would raise the highest rate from 4.8% to 8.4%, initially for wealthy filers. Jon Caldara of the Independence Institute has discovered that the drafters of the amendment blundered (intentionally?) by failing to index the tax brackets for inflation. Caldara says this is a stealth scheme to “raise taxes on everyone in Colorado over time.”

This is called “bracket creep,” which throughout the 1970s pushed middle-class Americans into higher federal tax rates. The federal government eliminated this sneaky annual tax hike with the 1981 Reagan tax cuts.

Even more problematic is that the tax may make it harder for the Denver Broncos to win another Super Bowl. Under the new tax the Broncos’ superstars pay a 8.4% penalty on their salary-capped talent compared to non-income-taxed states.