School attorneys said the poorest 15 percent of Texas school districts receive about $43,000 less per classroom than the wealthiest 15 percent, on average.

The system that Texas uses to fund its public schools violates the state’s constitution by not providing enough money to school districts and failing to distribute the money fairly, a judge ruled Feb. 4 in a landmark decision that could force the state Legislature to overhaul the way it pays for education.

Moments after closing arguments in his packed courtroom, state District Judge John Dietz ruled the school funding mechanism does not meet the Texas Constitution’s requirements for a fair and efficient system that provides a “general diffusion of knowledge.”

He declared that school funding was inadequate and that there were wide discrepancies in state support received by school districts in wealthy parts of Texas versus those in poorer areas. He also said the system is tantamount to an income tax, which is forbidden by the state constitution.

It was the second time in less than a decade that the state has been ordered to remake its school funding system. Dietz said he would issue a written ruling elaborating on his announcement in about a month. The state then can appeal the case directly to the Supreme Court, which could order the Legislature to remake the system.

But a ruling from the high court is not likely to come until the end of the legislative session in May, meaning Gov. Rick Perry would need to call a special session in 2014. In the interval, the state’s school funding system remains unchanged.

This was the sixth case of its kind since 1984. During a round of litigation eight years ago, Dietz issued a similar ruling, but the all-Republican Supreme Court reversed his findings on school funding—while still declaring the system unconstitutional because it violated state guarantees against an income tax.

This time around, more than 600 school districts across Texas responsible for educating three-quarters of the state’s 5 million-plus public school students sued. At issue were $5.4 billion in cuts to schools and education grant programs the Legislature imposed in 2011—but the districts said simply restoring that funding won’t be enough to fix a fundamentally flawed system.

“It’s not just dollars, it’s how we use them,” David Thompson, an attorney representing school districts that educate about 2 million students, said in reaction to Dietz’s ruling. “I think there’s a lot of room there to begin a discussion with the Legislature.”

The districts noted that the cuts came as the state requires schools to prepare students for standardized tests that are getting more difficult, and amid a statewide boom in the number of low-income students and those who need extra instruction to learn English—both of whom are more costly to educate.

(Next page: More details about the ruling)