Essentially, the school would be setting themselves up for a huge lawsuit. School districts are mandated by federal law to provide services for students or risk getting in trouble for non-compliance. However, the money used to fund special education programs is, by and large, funded through state budgets. I know my state cut funds to every corner of education, including special education. Have they violated the law? Yes, but it's such a tenuous situation: It's not fair to put the burden solely on states to fund but it's not exactly a good thing to let the federal government dictate what should be done in public school (No Child Left Behind, anyone?).
I would guess most school districts would cut other programs before they would cut special education programs. The risk of getting sued would probably loom too large.
"Aut dosce, aut disce, aut discede" - Latin Proverb
"I am the Grammarian about whom your
mother warned you."