Last week a South Carolina Senate Education Subcommittee debated SB 556, which would create a new private school voucher program. Before the hearing, Americans United sent a letter to the committee telling its members to reject the bill because vouchers have been shown to harm students’ academic achievement, fail students with disabilities and violate religious freedom.

Sensing that a statewide voucher would be unpopular, some senators offered to make the program a temporary “pilot” or to limit its eligibility to a “narrow” population of students. Hopefully, South Carolina’s legislators won’t buy this false compromise.

Limiting the voucher program is a tactic that we’ve seen before. Pro-voucher legislators often write voucher bills so that the program will end after a few years or so that only a small, vulnerable group of students, such as students with special needs or students from low-income families, qualify. Voucher proponents then use the limited scope of the programs to convince skeptical legislators to support the program as a trial run. Pro-voucher groups, however, know that “temporary” programs never end and “narrow” programs get expanded.

In fact, when Congress was debating a five-year pilot voucher for military-connected students in 2012, then-Rep. Randy Forbes (R-Va.) vocally opposed funding for the voucher, even though he expressed support for the voucher program itself. He noted that pilot programs inevitably turn into permanent programs: “Once this gets into law, nobody is going to want to repeal it.” Experience across the country shows that Forbes was right.

Washington, D.C.’s private school voucher program was adopted as a five-year pilot. But despite substantial evidence demonstrating that the program has been ineffective and unaccountable to taxpayers, it still exists 12 years after it was set to expire.

Florida passed its first voucher program in 1999, and it served just six students in its first year. Now, Florida has five voucher programs and nearly 150,000 voucher students. Spending has similarly increased. The Florida Tax Credit voucher was capped at $50 million when it passed in 2001, but the 2018-2019 cap is $873 million. And the voucher program passed last year could itself drain nearly $1 billion more from public schools over the next five years.

Like Florida, Arizona has five voucher programs. Its first voucher program ballooned from 128 students in its first year in 1997 to more than 52,000 students in 2016. In 2017, the legislature voted to make all of Arizona’s 1.1 million students eligible for one voucher program that served only 3,000 students. Thanks to Save Our Schools Arizona, the people of Arizona overturned this voucher expansion 65 percent-35 percent through a statewide ballot initiative.

Pro-voucher groups know that voucher bills can be difficult to pass, so they are willing to start with small programs and push to expand them in subsequent years. But these expansions come at the expense of our students and public schools: vouchers fund discrimination, do not improve academic achievement and drain resources away from public schools that serve 90 percent of our students. State legislators, including the South Carolina education subcommittee, should keep this in mind and reject any voucher bill, pilot program or not.