TALLAHASSEE, Fla. — Democratic lawmakers called Thursday for Education Commissioner Richard Corcoran to place new stipulations on private schools receiving funds from Florida's Corporate Tax Credit Scholarship voucher program.

It’s a step they call necessary after the revelation that dozens of the schools funded by the program have policies barring the enrollment of gay and transgender students.

Here's what you should know about the controversy: 

1. What is the Corporate Tax Credit Scholarship program?

The brainchild of former Republican Gov. Jeb Bush, it allows corporations to receive a discount on their state taxes in return for donating to Step Up For Students, the organization overseeing the voucher program.

Because funding for the vouchers doesn't come directly from state coffers, the program doesn't run afoul of prohibitions on using public funds to pay for private education.

2. How many recipient schools have anti-LGBT policies?

According to an Orlando Sentinel investigation, 156 Christian schools profess the view that homosexuality is an immoral offense. Of those, 83 have been found to have policies forbidding the admission of gay and transgender students.

If an admitted student is found to have a sexual orientation objectionable to administrators, many of the schools require expulsion.

3. What exactly do Democrats want Corcoran to do?

At a Capitol press conference Thursday, Orlando Democratic Reps. Carlos Guillermo Smith and Anna Eskamani, and St. Petersburg Democratic Sen. Darryl Rouson called on Corcoran to require private schools receiving voucher funding to accept all students, regardless of sexual orientation. They said they would speak with the commissioner by phone Thursday night.

"Commissioner Corcoran can decide that this is an issue that needs to be addressed, and he can help us fix it by directing the Step Up program to revise their policy so that we are no longer steering taxpayer resources to schools who have said in writing that they will expel gay or transgender students," Guillermo Smith told reporters.

4. How have corporate donors been reacting?

Four donors to the program -- Allegiant Airlines, Rosen Hotels, Fifth Third Bank, and Wells Fargo -- have announced they will no longer contribute because the schools' anti-LGBTQ stances don't comport with their own anti-discrimination policies.

5. What about Republican lawmakers?

While Democratic legislation to forbid voucher recipient schools from denying admission on the basis of sexual orientation has yet to receive a hearing, Senate President Bill Galvano (R-Bradenton) now supports reforming the scholarship program and is in talks with Step Up For Students.