Probably more than we know. There's a good reason they worked to kill a charter transparency and accountability bill.

Aspiration: Charter schools will be run by teachers and parents, thus escaping bureaucracy.
Reality: Charter boards are nearly always composed of unelected individuals who may not even live in the state in which the charter is located.

Reality: Authorizer laws, which vary by state, have resulted in a steady stream of income for authorizers, weak oversight, and, in some states, authorizer shopping that allows failed schools to continue.

Aspiration: Renewable charter contracts with supervision provided by outside authorizers will create schools accountable to families and the public.

Aspiration: Charter schools will be teacher-led schools, rooted in community needs..
Reality: About half of all charter schools are run by charter management organizations—some for-profit corporations; others nonprofit. All are
disconnected from families and communities.