The contract, reached after prolonged negotiations with the Oakland Education Association, includes raises that union and district leaders described as necessary to retain teachers in a region where housing costs have pushed educators out for years. What neither side has clearly answered is where the money comes from.

Oakland Unified has a history that makes this more than a bookkeeping problem. The district operated under state receivership from 2003 to 2009 after a fiscal collapse, and it has carried a state emergency loan — at one point more than $100 million — for years since. A new structural deficit tied to a labor commitment the district cannot demonstrate it can pay would put that history back in play.

The district has not publicly released a detailed multi-year budget projection showing how the raises are absorbed. State law requires school districts to certify they can meet obligations for the current and two subsequent fiscal years. Whether Oakland Unified can make that certification with the new contract on the books is the question that matters most right now, and it has not been answered in public.

The Alameda County Office of Education oversees Oakland Unified's finances and has the authority to intervene if the district cannot certify solvency. Watch for the district's next interim budget report, which will show whether county officials flag the contract as a threat to fiscal certification. The deadline for the second interim report is March 15.