A judge has refused to block voters from getting the last word on whether they want to expand a system of vouchers that uses public funds to send children to private and parochial schools.

In a six-page ruling made public Tuesday, Maricopa County Superior Court Judge Margaret Mahoney ruled that the law in effect last year when the referendum was filed did not give individuals the right to challenge petition drives. She pointed out it was repealed in 2015.

Mahoney acknowledged that lawmakers did vote to reinstate the individual challenge law last year. And that change took effect on Aug. 9, 2017.

But the judge pointed out that the petitions demanding a public vote were turned in on Aug. 8. Quite simply, Mahoney said, there is no legal basis for the challenge.

The judge also rejected the contention by voucher supporters that some of the petitions had to be thrown out — along with all the signatures on them — because the required signature of the person notarizing the document does not precisely match the name on the notary’s official stamp. Mahoney said that’s not the way the law reads.

And Mahoney also rejected the contention that some petition circulators made false statements to would-be signers about what the voucher expansion law would do if allowed to take effect, including that it would be the rich who benefit. The judge said voucher supporters, in filing suit, did not identify who made such statements, to whom they were made, how they were false, and whether the person who heard the comments relied on the statements in signing the petitions.

Attorney Tim La Sota, who represents voucher supporters, vowed an appeal. He said that, despite Mahoney’s ruling, Save Our Schools Arizona, which gathered sufficient signatures to force a public vote “did not successfully make the ballot and many of the things they did were in serious violation of the law.”

But unless her ruling is overturned, Mahoney’s order means voters will get to decide if there will be a big expansion in who is eligible to get a voucher of state funds to attend private and parochial schools.

That, in turn, will lead to an expensive and extensive campaign by voucher supporters, including Gov. Doug Ducey who signed the measure into law and who is likely to call on out-of-state friends to finance the effort.

Just this past weekend, the governor attended an event in California for major donors hosted by the Koch brothers, who are big supporters of vouchers.

The Washington Post, reporting on the event, said Ducey told those in attendance that what was enacted in Arizona is far more extensive than anything tried elsewhere. He also warned that if the measure goes to the ballot and voters reject the expansion, that could constitutionally preclude lawmakers from addressing the issue again.

“This is a very real fight in my state,” the Post reported Ducey as telling those in the Koch network, which is composed of major donors to conservative causes.

“This is a very real fight in my state,” the governor said. “I didn’t run for governor to play small ball.”

Arizona lawmakers first approved vouchers in 2011 to aid students with disabilities whose parents said they could not get their needs met in public schools.

Parents of eligible children were given what are formally known as “empowerment scholarship accounts,” essentially vouchers of state dollars to pay for tuition, tutoring and other needs.

Since that time, supporters have widened eligibility incrementally to where vouchers are now available to foster children, residents of Indian reservations and any student attending a school rated D or F.

About 3,500 children now get such vouchers.

Last year, Sen. Debbie Lesko, R-Peoria, pushed through legislation to remove all the restrictions, essentially making vouchers available to all 1.1 million students in Arizona public schools.

That proved to be a step too far for even some voucher supporters. So what was finally approved by the Republican-controlled Legislature and signed by Gov. Doug Ducey eliminates eligibility barriers but places a cap of 30,000 vouchers by 2023.

What happened then is that foes of the expansion used a provision in the Arizona Constitution which gives those opposed to any legislative action 90 days after the end of the session to gather sufficient signatures to refer the measure to the ballot.

That’s what happened here, with Save Our Schools Arizona submitting more than 110,000 signatures. Secretary of State Michele Reagan found that the petitions had more than the minimum 75,321 valid signatures needed and put the measure on the November ballot as Proposition 305.

The successful petition drive also keeps the law from taking effect until voters get a chance to ratify or reject what lawmakers enacted.

Tuesday’s ruling is unlikely the last word — and not just because voucher supporters are likely to appeal.

The entire referendum could be undermined if the Republican-controlled Legislature makes even a one-word change this session in the 2017 law. That would force opponents of expanded vouchers to start all over again gathering signatures to put the issue on the November ballot.