The case against Douglas County School District's pilot program that offers students the opportunity to attend private schools using public funding began in a Denver district courtroom Tuesday morning.The ACLU -- along with concerned parents -- filed a lawsuit in late June seeking an injunction to stop the program. Tuesday morning, their attorneys argued in their opening statements that the Choice Scholarship Program violated Colorado's state Constitution.The basis of their argument focused on the fact that public tax money would essentially be used to pay for private schools that are in many cases religious. They said that because private schools can make hiring and admissions decisions based on religious beliefs, they should not be in the position to receive public funding. They also said that religious schools could not require classes such as theology as a requirement for graduation if they received public funding.In their opening arguments, attorneys representing Douglas County School District , the Colorado Board of Education, and parents of students who were granted scholarships -- claimed that the program would save the district about $350,000 at a time when budget cuts were crippling the schools. They also said the process of approving the program had been "open and inclusive," allowing the public to give the school board adequate feedback.While attorneys for those who filed the suit assured the judge they were not asking for any of the money paid out to parents so far to be returned, the defense argued that the lawsuit had been filed too late. More than 200 of the 500 students approved for the program had already received initial funding.In fact, Woodlands Academy in Castle Rock, which is a nonsectarian school, had already hired two new teachers and built new classrooms in expectation of 10 new students from the scholarship program.Cindra Barnard, who has been active in Douglas County schools for years, was one of the parents who filed suit against the district. Her son will be a senior at Highlands Ranch High School."If it flies in DougCo it'll fly in Denver, it'll fly in JeffCo and Adams County and we will have established a two-tiered system of education," Barnard said. "And it's absolutely wrong. Public tax dollars should not be funding private education. It sets up a program where only the wealthy can afford it."Barnard told 7NEWS that she did not have a problem with private schools, but she did have a problem with taxpayer funds leaving the public schools to help students attend private schools. She said the estimated $3 million that would be taken from public school coffers would hurt the quality of education for students like her son.Even more, she was concerned that the program would set a precedent in other districts."I look at this program as a slippery slope," Barnard said.Father of three Kevin Leung, who was also listed as a plaintiff, worried claims that the program would save the district money could not be substantiated."This taking money from public schools and funding private and religious schools is going to cost the district precious resources," said Leung.Testimony from witnesses for the defense was scheduled for Wednesday.Several parents appeared on the list of defendants, including Diana Oakley, whose 13-year-old son Nathaniel was accepted into the Choice Scholarship Program. Nathaniel suffers from an extreme form of autism known as Asperger's and has struggled in public schools. Nathaniel was accepted into Humanex Academy in Denver, where teachers specialize in working with autistic students. Oakley said without the scholarship, she could not afford the special help Nathaniel needs."I just have not been able to get enough help for Nathaniel to make it worth his while," Oakley said. "There's this hour-glass and the time is just running out. It's running out on us."Oakley said the private academy starts the fall semester Aug. 15."You know we only get one chance at his education, and I don't want the sand to run out on him," Oakley said.Her two other children were thriving in Douglas County schools, Oakley said, but that the choice to send Nathaniel to a private school would also benefit his former classmates in public schools. She said removing him would free up teachers to give more attention to the other students who did not need such specialized instruction.The Douglas County School Board approved the Choice Scholarship Program March 15. It would provide about $4,500 for each of the 500 students accepted to use at private schools of their choosing. That amount is roughly 75 percent of the revenue the district receives for each pupil.On Tuesday, Denver District Court Judge Michael Martinez ruled that the plaintiff was requesting relief consistent with a mandatory injunction. Martinez said his ruling was necessary because a court order could put a permanent stop to the program. The ruling increased the burden of proof on attorneys for the plaintiffs.A decision on the case was expected by Thursday.