In a letter to Republican House Speaker Tim Jones, Koster, a Democrat, confirmed the governor's position that the bill could retroactively award tax refunds to Missourians who paid taxes the last three years.
"In the opinion of this Office, the plain language of the new
legislation suggests that, if certain triggering events set forth in the
statute occur, taxpayers may seek refunds of taxes paid in the three
preceding tax years," Koster said.
The argument that the state's current budget could have to pay for tax cuts from previous years was one of the governor's arguments for withholding about $400 million in appropriations for agencies, mostly from higher education and education.
"With a price tag of at least $800 million, House Bill 253 contains flawed provisions that would explode these costs immediately - to the tune of $1.2 billion - if Washington passes the Federal Marketplace Fairness Act," Nixon said when announcing the withholding.
Republican Party spokesman Matt Wills spoke out against the letter and said the governor and his staff acted in "bad faith" during the legislative session by not working with the Republican-led House during the creation of the bill. He added the letter was just rhetoric.
"It's very difficult to understand why he would do that," Wills said about the veto. "He simply thinks he can spend taxpayer money better than the taxpayers."
Koster's opinion focuses on a provision that creates a tax reduction if Congress passes a pending law letting states impose taxes on internet sales. If that federal law is passed, Koster concluded that the reduction would cover not just the current year, but all prior tax years for the entire history of Missouri -- although state law provides that a taxpayer can file an amended return, seeking back tax refunds, for no more than three years.
The letter was written in response to a request from Jones and came on Aug. 29, the same day that Texas Republican Gov. Rick Perry was addressing groups in St. Louis promoting efforts to override Nixon's veto.Nixon spent the day traveling across the state in his ongoing campaign speaking against the bill.
Koster's opinion did not discourage the tax cut's sponsor - Rep. T.J. Berry, R-Kearney - who renewed a call for an override Aug. 29.
Berry also called for a special session concurrent with the veto session in the event that the override vote fails. He said he is open to fixing concerns lawmakers have with the bill including the potential tax increases on prescription drugs and textbooks.
The Legislature meets Sept. 11 to take up bills vetoed by the governor.