Gov. Sam Brownback on Wednesday defended his proposal to do away with the state school finance formula, saying it’s one of the reasons the state is facing a large revenue shortfall this year.

He also subtly laid part of the blame on the Kansas State Department of Education for giving estimates of how much the formula would cost this year, estimates that later turned out to be too low.

“We have proposed stable funding for K-12 as appropriated in FY ’15, which included an increase of approximately $200 million,” Brownback said in a statement released Wednesday afternoon. “The previous Kansas State Department of Education estimate for the 2014-2015 school year was understated by more than $60 million.”

That is partially true, although the agency had warned legislators last year that its estimates were only best guesses because nobody could predict at the time how districts would respond to new funding made available as a result of a Kansas Supreme Court order.

In March, the Supreme Court upheld part of a lower court ruling that said the state’s failure to fully fund so-called “equalization” aid for poor school districts was unconstitutional. It ordered the Legislature to fully fund equalization for local option budgets, which lawmakers had held flat during the Great Recession, as well as capital outlay equalization, which the Legislature had stopped funding altogether.

Lawmakers agreed to fully fund those two aid programs, but it was not clear at the time how districts would respond. That’s because school districts don’t set their budgets until August each year, after they know for certain how much funding they can expect from the state.

The department had estimated at the time that the increased aid would cost about $119 million. But as it turned out, a lot of districts that had cut back in those areas when the Legislature wasn’t fully funding equalization took advantage of the new funding available this year by raising their LOB and capital outlay budgets.

That resulted in about $64 million in unexpected costs to the state.

“The Legislature cannot properly budget state resources when an unpredictable formula, responsible for more than half of our state general fund expenditures, is complicated by incorrect information,” Brownback said. “This is exactly the reason why a new formula is necessary.”

Brownback has proposed to fund that extra $64 million this year. But his budget proposal for the next two fiscal years strikes that money out. That’s part of the $127 million cut that K-12 schools would take in their operating budgets each of the next two years under Brownback’s plan.

Brownback’s plan calls for lumping base state aid and the two kinds of equalization aid into one lump sum and distributing it to districts in the form of block grants for the next two years. Those block grants are based on the current fiscal year’s funding, minus the $64 million in additional costs this year, and minus some of next year’s increased pension contributions.

Democrats, moderate Republicans and other education advocates are saying it doesn’t matter whether the Legislature uses a formula to distribute the money or not. That’s because a three-judge trial court in December ruled that the overall level of funding for public schools is already unconstitutionally low, and the cuts in Brownback’s budget proposal would only make that situation worse.

The adequacy of overall funding was a question the Supreme Court had referred back to the trial court last year for reconsideration.